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  • 301.
    Alp, Dennis
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Fysik.
    Demory, B-O
    Refraction in exoplanet atmospheres Photometric signatures, implications for transmission spectroscopy, and search in Kepler data2018Ingår i: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 609, artikel-id A90Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Context. Refraction deflects photons that pass through atmospheres, which affects transit light curves. Refraction thus provides an avenue to probe physical properties of exoplanet atmospheres and to constrain the presence of clouds and hazes. In addition, an effective surface can be imposed by refraction, thereby limiting the pressure levels probed by transmission spectroscopy. Aims. The main objective of the paper is to model the effects of refraction on photometric light curves for realistic planets and to explore the dependencies on atmospheric physical parameters. We also explore under which circumstances transmission spectra are significantly affected by refraction. Finally, we search for refraction signatures in photometric residuals in Kepler data. Methods. We use the model of Hui & Seager (2002, ApJ, 572, 540) to compute deflection angles and refraction transit light curves, allowing us to explore the parameter space of atmospheric properties. The observational search is performed by stacking large samples of transit light curves from Kepler. Results. We find that out-of-transit refraction shoulders are the most easily observable features, which can reach peak amplitudes of similar to 10 parts per million (ppm) for planets around Sun-like stars. More typical amplitudes are a few ppm or less for Jovians and at the sub-ppm level for super-Earths. In-transit, ingress, and egress refraction features are challenging to detect because of the short timescales and degeneracies with other transit model parameters. Interestingly, the signal-to-noise ratio of any refraction residuals for planets orbiting Sun-like hosts are expected to be similar for planets orbiting red dwarfs and ultra-cool stars. We also find that the maximum depth probed by transmission spectroscopy is not limited by refraction for weakly lensing planets, but that the incidence of refraction can vary significantly for strongly lensing planets. We find no signs of refraction features in the stacked Kepler light curves, which is in agreement with our model predictions.

  • 302.
    Alp, Dennis
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Larsson, Josefin
    Blasts from the Past: Supernova Shock Breakouts among X-Ray Transients in the XMM-Newton Archive2020Ingår i: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 896, nr 1, artikel-id 39Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The first electromagnetic signal from a supernova (SN) is released when the shock crosses the progenitor surface. This shock breakout (SBO) emission provides constraints on progenitor and explosion properties. Observationally, SBOs appear as minute- to hour-long extragalactic X-ray transients. They are challenging to detect and only one SBO has been observed to date. Here, we search the XMM-Newton archive and find 12 new SN SBO candidates. We identify host galaxies to nine of these at estimated redshifts of 0.1-1. The SBO candidates have energies of similar to 10(46)erg, timescales of 30-3000 s, and temperatures of 0.1-1 keV. They are all consistent with being SN SBOs, but some may be misidentified Galactic foreground sources or other extragalactic objects. SBOs from blue supergiants agree well with most of the candidates. However, a few could be SBOs from Wolf-Rayet stars surrounded by dense circumstellar media, whereas two are more naturally explained as SBOs from red supergiants. The observations tentatively support non-spherical SBOs and are in agreement with asymmetries predicted by recent three-dimensional SN explosion simulations. eROSITA may detect similar to 2 SBOs per year, which could be detected in live analyses and promptly followed up.

  • 303.
    Alp, Dennis
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Larsson, Josefin
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Fransson, Claes
    Stockholm Univ, AlbaNova, Dept Astron, Oskar Klein Ctr, SE-10691 Stockholm, Sweden..
    Thermal Emission and Radioactive Lines, but No Pulsar, in the Broadband X-Ray Spectrum of Supernova 1987A2021Ingår i: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 916, nr 2, artikel-id 76Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Supernova 1987A offers a unique opportunity to study an evolving supernova in unprecedented detail over several decades. The X-ray emission is dominated by interactions between the ejecta and the circumstellar medium, primarily the equatorial ring (ER). We analyze 3.3.Ms of NuSTAR data obtained between 2012 and 2020, and two decades of XMM-Newton data. Since similar to 2013, the flux below 2.keV has declined, the 3-8.keV flux has increased but has started to flatten, and the emission above 10.keV has remained nearly constant. The spectra are well described by a model with three thermal shock components. Two components at 0.3 and 0.9.keV are associated with dense clumps in the ER, and a 4.keV component may be a combination of emission from diffuse gas in the ER and the surrounding low-density H II region. We disfavor models that involve nonthermal X-ray emission and place constraints on nonthermal components, but cannot firmly exclude an underlying power law. Radioactive lines show a Ti-44 redshift of 670(+520) (-380) km s(-1), Ti-44 mass of ' 1.73(-0.29)(+0.27) 10(-4) M-circle dot, and Fe-55Y mass of <4.2 10(-4) M-circle dot. The 35-65.keV luminosity limit on the compact object is 2 ' 1034.erg.s-1, and < 15% of the 10-20.keV flux is pulsed. Considering previous limits, we conclude that there are currently no indications of a compact object, aside from a possible hint of dust heated by a neutron star in recent ALMA images.

  • 304.
    Alp, Dennis
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Larsson, Josefin
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Fransson, Claes
    Thermal Emission and Radioactive Lines, but No Pulsar, in the Broadband X-Ray Spectrum of Supernova 1987AManuskript (preprint) (Övrigt vetenskapligt)
  • 305.
    Alp, Dennis
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik. The Oskar Klein Centre, AlbaNova, SE-106 91 Stockholm, Sweden.
    Larsson, Josefin
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik. The Oskar Klein Centre, AlbaNova, SE-106 91 Stockholm, Sweden.
    Maeda, Keiichi
    Kyoto Univ, Dept Astron, Sakyo Ku, Kitashirakawa Oiwake Cho, Kyoto 6068502, Japan..
    Fransson, Claes
    Stockholm Univ, Oskar Klein Ctr, Dept Astron, AlbaNova, SE-10691 Stockholm, Sweden..
    Wongwathanarat, Annop
    Max Planck Inst Astrophys, Karl Schwarzschild Str 1, D-85748 Garching, Germany..
    Gabler, Michael
    Max Planck Inst Astrophys, Karl Schwarzschild Str 1, D-85748 Garching, Germany..
    Janka, Hans-Thomas
    Max Planck Inst Astrophys, Karl Schwarzschild Str 1, D-85748 Garching, Germany..
    Jerkstrand, Anders
    Max Planck Inst Astrophys, Karl Schwarzschild Str 1, D-85748 Garching, Germany..
    Heger, Alexander
    Monash Univ, Monash Ctr Astrophys, Sch Phys & Astron, Clayton, Vic 3800, Australia.;Tsung Dao Lee Inst, Shanghai 200240, Peoples R China..
    Menon, Athira
    Univ Amsterdam, Anton Pannekoek Inst Astron, NL-1090 GE Amsterdam, Netherlands..
    X-Ray and Gamma-Ray Emission from Core-collapse Supernovae: Comparison of Three-dimensional Neutrino-driven Explosions with SN 1987A2019Ingår i: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 882, nr 1, artikel-id 22Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    During the first few hundred days after the explosion, core-collapse supernovae (SNe) emit down-scattered X-rays and gamma-rays originating from radioactive line emissions, primarily from the Ni-56 -> Co-56 -> Fe-56 chain. We use supernova (SN) models based on three-dimensional neutrino-driven explosion simulations of single stars and mergers to compute this emission and compare the predictions with observations of SN 1987A. A number of models are clearly excluded, showing that high-energy emission is a powerful way of discriminating between models. The best models are almost consistent with the observations, but differences that cannot be matched by a suitable choice of viewing angle are evident. Therefore, our self-consistent models suggest that neutrino-driven explosions are able to produce, in principle, sufficient mixing, although remaining discrepancies may require small changes to the progenitor structures. The soft X-ray cutoff is primarily determined by the metallicity of the progenitor envelope. The main effect of asymmetries is to vary the flux level by a factor of similar to 3. For the more asymmetric models, the shapes of the light curves also change. In addition to the models of SN 1987A, we investigate two models of SNe II-P and one model of a stripped-envelope SN IIb. The Type II-P models have observables similar to those of the models of SN 1987A, but the stripped-envelope SN model is significantly more luminous and evolves faster. Finally, we make simple predictions for future observations of nearby SNe.

  • 306.
    Alsayfi, Majed S.
    et al.
    King Abdelaziz Univ, Fac Comp & Informat Technol, Dept Comp Sci, Jeddah 21589, Saudi Arabia..
    Dahab, Mohamed Y.
    King Abdelaziz Univ, Fac Comp & Informat Technol, Dept Comp Sci, Jeddah 21589, Saudi Arabia..
    Eassa, Fathy E.
    King Abdelaziz Univ, Fac Comp & Informat Technol, Dept Comp Sci, Jeddah 21589, Saudi Arabia..
    Salama, Reda
    King Abdelaziz Univ, Fac Comp & Informat Technol, Dept Informat Technol, Jeddah 21589, Saudi Arabia..
    Haridi, Seif
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Datavetenskap, Programvaruteknik och datorsystem, SCS.
    Al-Ghamdi, Abdullah S.
    King Abdelaziz Univ, Fac Comp & Informat Technol, Dept Comp Sci, Jeddah 21589, Saudi Arabia.;King Abdelaziz Univ, Fac Comp & Informat Technol, Dept Informat Technol, Jeddah 21589, Saudi Arabia..
    Big Data in Vehicular Cloud Computing: Review, Taxonomy, and Security Challenges2022Ingår i: ELEKTRONIKA IR ELEKTROTECHNIKA, ISSN 1392-1215, Vol. 28, nr 2, s. 59-71Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Modern vehicles equipped with various smart sensors have become a means of transportation and have become a means of collecting, creating, computing, processing, and transferring data while traveling through modern and rural cities. A traditional vehicular ad hoc network (VANET) cannot handle the enormous and complex data that are collected by modern vehicle sensors (e.g., cameras, lidar, and global positioning systems (GPS)) because they require rapid processing, analysis, management, storage, and uploading to trusted national authorities. Furthermore, the integrated VANET with cloud computing presents a new concept, vehicular cloud computing (VCC), which overcomes the limitations of VANET, brings new services and applications to vehicular networks, and generates a massive amount of data compared to the data collected by individual vehicles alone. Therefore, this study explored the importance of big data in VCC. First, we provide an overview of traditional vehicular networks and their limitations. Then we investigate the relationship between VCC and big data, fundamentally focusing on how VCC can generate, transmit, store, upload, and process big data to share it among vehicles on the road. Subsequently, a new taxonomy of big data in VCC was presented. Finally, the security challenges in big data-based VCCs are discussed.

  • 307.
    Alvarez Melcon, A.
    et al.
    Tech Univ Cartagena, Dept Informat & Commun Technol, Murcia 30203, Spain..
    Cuendis, S. Arguedas
    European Org Nucl Res CERN, CH-1211 Geneva 23, Switzerland..
    Cogollos, C.
    Univ Barcelona, Inst Ciencias Cosmos, Barcelona 08028, Spain..
    Diaz-Morcillo, A.
    Tech Univ Cartagena, Dept Informat & Commun Technol, Murcia 30203, Spain..
    Doebrich, B.
    European Org Nucl Res CERN, CH-1211 Geneva 23, Switzerland..
    Gallego, J. D.
    Natl Ctr Radioastron Technol & Geospace Applicat, Yebes Observ, Guadalajara 19080, Spain..
    Garcia Barcelo, J. M.
    Tech Univ Cartagena, Dept Informat & Commun Technol, Murcia 30203, Spain..
    Gimeno, B.
    Univ Valencia, CSIC, Inst Fis Corpuscular IFIC, Valencia 46071, Spain..
    Golm, J.
    European Org Nucl Res CERN, CH-1211 Geneva 23, Switzerland.;Friedrich Schiller Univ Jena, Inst Opt & Quantum Elect, Jena, Germany..
    Irastorza, I. G.
    Univ Zaragoza, CAPA, Zaragoza 50009, Spain.;Univ Zaragoza, Dept Fis Teor, Zaragoza 50009, Spain..
    Lozano-Guerrero, A. J.
    Tech Univ Cartagena, Dept Informat & Commun Technol, Murcia 30203, Spain..
    Malbrunot, C.
    European Org Nucl Res CERN, CH-1211 Geneva 23, Switzerland..
    Millar, Alexander
    Stockholm Univ, Oskar Klein Ctr Cosmoparticle Phys, Dept Phys, S-10691 Stockholm, Sweden.Stockholm Univ, Roslagstullsbacken 23, S-10691 Stockholm, Sweden.;Nordita SU.
    Navarro, P.
    Tech Univ Cartagena, Dept Informat & Commun Technol, Murcia 30203, Spain..
    Pena Garay, C.
    Univ Valencia, CSIC, I2SysBio, Valencia 46071, Spain.;Lab Subterraneo Canfranc, Estn Canfranc, Huesca 22880, Spain..
    Redondo, J.
    Univ Zaragoza, CAPA, Zaragoza 50009, Spain.;Univ Zaragoza, Dept Fis Teor, Zaragoza 50009, Spain.;Max Planck Inst Phys & Astrophys, Werner Heisenberg Inst, D-80805 Munich, Germany..
    Wuensch, W.
    European Org Nucl Res CERN, CH-1211 Geneva 23, Switzerland..
    Scalable haloscopes for axion dark matter detection in the 30 mu eV range with RADES2020Ingår i: Journal of High Energy Physics (JHEP), ISSN 1126-6708, E-ISSN 1029-8479, nr 7, artikel-id 84Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    RADES (Relic Axion Detector Exploratory Setup) is a project with the goal of directly searching for axion dark matter above the 30 mu eV scale employing custom-made microwave filters in magnetic dipole fields. Currently RADES is taking data at the LHC dipole of the CAST experiment. In the long term, the RADES cavities are envisioned to take data in the BabyIAXO magnet. In this article we report on the modelling, building and characterisation of an optimised microwave-filter design with alternating irises that exploits maximal coupling to axions while being scalable in length without suffering from mode-mixing. We develop the mathematical formalism and theoretical study which justifies the performance of the chosen design. We also point towards the applicability of this formalism to optimise the MADMAX dielectric haloscopes.

  • 308.
    Amati, L.
    et al.
    IASF Bologna, INAF, via P Gobetti 101, I-40129 Bologna, Italy..
    O'Brien, P.
    Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England..
    Gotz, D.
    Univ Paris Saclay, IRFU, CEA, Dept Astrophys, F-91191 Gif Sur Yvette, France..
    Bozzo, E.
    Univ Geneva, Dept Astron, Ch Ecogia 16, CH-1290 Versoix, Switzerland..
    Tenzer, C.
    Eberhard Karls Univ Tubingen, Inst Astron & Astrophys, Kepler Ctr Astro & Particle Phys, Abt Hochenergieastrophys, Sand 1, D-72076 Tubingen, Germany..
    Frontera, F.
    Univ Ferrara, Dept Phys & Earth Sci, Via Saragat 1, I-44122 Ferrara, Italy.;INAF IASF, Via Gobetti 101, I-40129 Bologna, Italy..
    Ghirlanda, G.
    Osserv Astron Brera, INAF, Via E Bianchi 46, I-23807 Merate, LC, Italy..
    Labanti, C.
    IASF Bologna, INAF, via P Gobetti 101, I-40129 Bologna, Italy..
    Osborne, J. P.
    Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England..
    Stratta, G.
    Univ Urbino Carlo Bo, I-61029 Urbino, Italy..
    Tanvir, N.
    Univ Leicester, Dept Phys & Astron, Univ Rd, Leicester LE1 7RH, Leics, England.;Univ Leicester, Leicester Inst Space & Earth Observat, Univ Rd, Leicester LE1 7RH, Leics, England..
    Willingale, R.
    Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England..
    Attina, P.
    GP Adv Projects, Gussago, Italy..
    Campana, R.
    IASF Bologna, INAF, Via Piero Gobetti 101, I-40129 Bologna, Italy..
    Castro-Tirado, A. J.
    CSIC, IAA, POB 03004, E-18080 Granada, Spain..
    Contini, C.
    OHB Italia, Via Gallarate 150, I-20151 Milan, Italy..
    Fuschino, F.
    IASF Bologna, INAF, via P Gobetti 101, I-40129 Bologna, Italy..
    Gomboc, A.
    Univ Nova Gorica, Ctr Astrophys & Cosmol, Vipayska 11c, Ajdov V Sv cina 5270, Slovenia..
    Hudec, R.
    Czech Tech Univ, Fac Elect Engn, Prague 16627, Czech Republic.;Kazan Fed Univ, Kazan 420008, Russia..
    Orleanski, P.
    Polish Acad Sci, Space Res Ctr, Warsaw, Poland..
    Renotte, E.
    Ctr Spatial Liege, Parc Sci Sart Tilman Ave Pre Aily, B-4031 Angleur Liege, Belgium..
    Rodic, T.
    Slovenian Ctr Excellence Space Sci & Technol, SPACE SI, Ljubljana, Slovenia..
    Bagoly, Z.
    Eotv Os Univ, Budapest, Hungary..
    Blain, A.
    Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England..
    Callanan, P.
    Univ Coll Cork, Dept Phys, Cork, Ireland..
    Covino, S.
    Brera Astron Observ, INAF, Via Bianchi 46, I-23807 Merate, LC, Italy..
    Ferrara, A.
    Scuola Normale Super Pisa, Piazza Cavalieri 7, I-56126 Pisa, Italy.;Univ Tokyo, Kavli IPMU, 5-1-5 Kashiwanoha, Kashiwa, Chiba 2778583, Japan..
    Le Floch, E.
    Univ Paris Saclay, IRFU, CEA, Dept Astrophys, F-91191 Gif Sur Yvette, France..
    Marisaldi, M.
    IASF Bologna, INAF, Via Piero Gobetti 101, I-40129 Bologna, Italy..
    Mereghetti, S.
    IASF Milano, INAF, Via E Bassini 15, I-20133 Milan, Italy..
    Rosati, P.
    Univ Ferrara, Via Saragat 1, Ferrara, Italy..
    Vacchi, A.
    INFN Trieste, Via Valerio 2, Trieste, Italy..
    D'Avanzo, P.
    Osserv Astron Brera, INAF, Via E Bianchi 46, I-23807 Merate, LC, Italy..
    Giommi, P.
    Italian Space Agcy, ASI, Via Politecn Snc, I-00133 Rome, Italy..
    Piranomonte, S.
    Osserv Astron Roma, INAF, Via Frascati 33, I-00040 Monte Porzio Catone, Italy..
    Piro, L.
    IAPS Roma, INAF, Via Fosso Cavaliere 100, I-00133 Rome, Italy..
    Reglero, V
    Univ Valencia, Image Proc Lab, C Catedrat Jose Beltran 2, Valencia 46980, Spain..
    Rossi, A.
    IASF Bologna, INAF, via P Gobetti 101, I-40129 Bologna, Italy..
    Santangelo, A.
    Eberhard Karls Univ Tubingen, Inst Astron & Astrophys, Kepler Ctr Astro & Particle Phys, Abt Hochenergieastrophys, Sand 1, D-72076 Tubingen, Germany..
    Salvaterra, R.
    Ist Astrofis Spaziale & Fis Cosm Milano, INAF, Via E Bassini 15, I-20133 Milan, Italy..
    Tagliaferri, G.
    Osserv Astron Brera, INAF, Via E Bianchi 46, I-23807 Merate, LC, Italy..
    Vergani, S.
    PSL Res Univ, Observ Paris, CNRS, GEPI, Pl Jules Janssen, F-92190 Meudon, France.;Osserv Astron Brera, INAF, Via Bianchi 46, I-23807 Merate, LC, Italy..
    Vinciguerra, S.
    Univ Birmingham, Inst Gravitat Wave Astron, Birmingham B15 2TT, W Midlands, England.;Univ Birmingham, Sch Phys & Astron, Birmingham B15 2TT, W Midlands, England..
    Briggs, M.
    Univ Alabama, Ctr Space Plasma & Aeron Res, 320 Sparkman Dr, Huntsville, AL 35805 USA..
    Campolongo, E.
    OHB Italia, Via Gallarate 150, I-20151 Milan, Italy..
    Ciolfi, R.
    Osserv Astron Padova, INAF, Vicolo Osservatorio 5, I-35122 Padua, Italy.;Trento Inst Fundamental Phys & Applicat, INFN TIFPA, Via Sommarive 14, I-38123 Trento, Italy..
    Connaughton, V
    Univ Space Res Assoc, NSSTC, 320 Sparkman Dr, Huntsville, AL 35805 USA..
    Cordier, B.
    Univ Paris Saclay, IRFU, CEA, Dept Astrophys, F-91191 Gif Sur Yvette, France..
    Morelli, B.
    OHB Italia, Via Gallarate 150, I-20151 Milan, Italy..
    Orlandini, M.
    IASF Bologna, INAF, Via Piero Gobetti 101, I-40129 Bologna, Italy..
    Adami, C.
    Aix Marseille Univ, LAM, CNRS, F-13388 Marseille, France..
    Argan, A.
    IAPS Roma, INAF, Via Fosso Cavaliere 100, I-00133 Rome, Italy..
    Atteia, J-L
    Univ Toulouse, UPS, CNRS, CNES,IRAP, Toulouse, France..
    Auricchio, N.
    IASF Bologna, INAF, via P Gobetti 101, I-40129 Bologna, Italy..
    Balazs, L.
    MTA CSFK Konkoly Observ, Konkoly Thege Mut 13-17, H-1121 Budapest, Hungary..
    Baldazzi, G.
    INFN, Sez Bologna, Viale Berti Pichat 6-2, I-40127 Bologna, Italy.;Univ Bologna, Dept Phys, Viale Berti Pichat 6-2, I-40127 Bologna, Italy..
    Basa, S.
    Aix Marseille Univ, LAM, CNRS, F-13388 Marseille, France..
    Basak, Rupal
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik. Oskar Klein Ctr Cosmoparticle Phys, SE-10691 Stockholm, Sweden.
    Bellutti, P.
    FBK, Via Sommarive 18, I-38123 Povo, Trento, Italy..
    Bernardini, M. G.
    Osserv Astron Brera, INAF, Via E Bianchi 46, I-23807 Merate, LC, Italy..
    Bertuccio, G.
    Politecn Milan, Via Anzani 42, I-22100 Como, Italy.;INFN Milano, Via Celoria 16, I-20133 Milan, Italy..
    Braga, J.
    INPE, Av Astronautas 1758, BR-12227010 Sao Jose Dos Campos, SP, Brazil..
    Branchesi, M.
    Univ Urbino Carlo Bo, Via A Saffi 2, I-61029 Urbino, Italy.;INFN, Sez Firenze, Via G Sansone 1, I-50019 Sesto Fiorentino, Italy..
    Brandt, S.
    DTU Space Natl Space Inst Elektrovej, Bldg 327, DK-2800 Lyngby, Denmark..
    Brocato, E.
    INAF Astron Teramo, I-64100 Teramo, Italy..
    Budtz-Jorgensen, C.
    DTU Space Natl Space Inst Elektrovej, Bldg 327, DK-2800 Lyngby, Denmark..
    Bulgarelli, A.
    IASF Bologna, INAF, Via Gobetti 101, I-40129 Bologna, Italy..
    Burderi, L.
    Univ Cagliari, Dipartimento Fis, SP Monserrato Sestu Km 0-7, I-09042 Monserrato, Italy..
    Camp, J.
    Goddard Space Flight Ctr, Astrophys Sci Div, Greenbelt, MD 20771 USA..
    Capozziello, S.
    Univ Napoli Federico II, Dipartimento Fis, Via Cinthia, I-80126 Naples, Italy..
    Caruana, J.
    Univ Malta, Dept Phys, Msida 2080, Msd, Malta.;Univ Malta, Inst Space Sci & Astron, Msida 2080, Msd, Malta..
    Casella, P.
    Osserv Astron Roma, INAF, Via Frascati 33, I-00040 Monte Porzio Catone, Italy..
    Cenko, B.
    NASA, Goddard Space Flight Ctr, Astrophys Sci Div, Mail Code 661, Greenbelt, MD 20771 USA.;Univ Maryland, Joint Space Sci Inst, College Pk, MD 20742 USA..
    Chardonnet, P.
    Univ Savoie, CNRS, LAPTh, BP 110, F-74941 Annecy Le Vieux, France.;Natl Res Nucl Univ MEPhI, 31 Kashirskoe Sh, Moscow 115409, Russia..
    Ciardi, B.
    Max Planck Inst Astrophys, Karl Schwarzschild Str 1, D-85741 Garching, Germany..
    Colafrancesco, S.
    Univ Witwatersrand, Sch Phys, Private Bag 3, ZA-2050 Johannesburg, South Africa..
    Dainotti, M. G.
    Stanford Univ, Dept Phys & Astron, Via Pueblo Mall 382, Stanford, CA 94305 USA.;INAF OAS Bologna, Via P Gobetti 93-3, Bologna, Italy.;Uniwersytet Jagiellonski, Obserwatorium Astron, Ul Orla 171, PL-31501 Krakow, Poland..
    D'Elia, V
    Osserv Astron Roma, INAF, Via Frascati 33, I-00040 Monte Porzio Catone, Italy.;Agenzia Spaziale Italiana, SSDC, Via Politecn Snc, I-00133 Rome, Italy..
    De Martino, D.
    Capodimonte Astron Observ Naples, INAF, Via Moiariello 16, I-80131 Naples, Italy..
    De Pasquale, M.
    Istanbul Univ, Dept Astron & Space Sci, TR-34119 Istanbul, Turkey..
    Del Monte, E.
    IAPS Roma, INAF, Via Fosso Cavaliere 100, I-00133 Rome, Italy..
    Della Valle, M.
    Osserv Astron Capodimonte, INAF, Salita Moiariello 16, I-80131 Naples, Italy.;Int Ctr Relativist Astrophys, Piazzale Repubbl 2, I-65122 Pescara, Italy..
    Drago, A.
    INFN, Via Enrico Fermi 40, Frascati, Italy..
    Evangelista, Y.
    IAPS Roma, INAF, Via Fosso Cavaliere 100, I-00133 Rome, Italy..
    Feroci, M.
    IAPS Roma, INAF, Via Fosso Cavaliere 100, I-00133 Rome, Italy..
    Finelli, F.
    IASF Bologna, INAF, via P Gobetti 101, I-40129 Bologna, Italy..
    Fiorini, M.
    Ist Astrofis Spaziale & Fis Cosm Milano, INAF, Via E Bassini 15, I-20133 Milan, Italy..
    Fynbo, J.
    Univ Copenhagen, Dark Cosmol Ctr, Niels Bohr Inst, Juliane Maries Vej 30, DK-2100 Copenhagen, Denmark..
    Gal-Yam, A.
    Weizmann Inst Sci, Fac Phys, Dept Particle Phys & Astrophys, IL-76100 Rehovot, Israel..
    Gendre, B.
    Univ Virgin Isl, 2 John Brewers Bay, St Thomas, VI 00802 USA.;Etelman Observ, Bonne Resolut, St Thomas, VI USA..
    Ghisellini, G.
    Osserv Astron Brera, INAF, Via E Bianchi 46, I-23807 Merate, LC, Italy..
    Grado, A.
    Capodimonte Astron Observ Naples, INAF, Via Moiariello 16, I-80131 Naples, Italy..
    Guidorzi, C.
    Univ Ferrara, Dept Phys & Earth Sci, Via Saragat 1, I-44122 Ferrara, Italy..
    Hafizi, M.
    Univ Tirana, Dept Phys, Tirana, Albania..
    Hanlon, L.
    Univ Coll Dublin, Sch Phys, Space Sci Grp, Dublin 4, Ireland..
    Hjorth, J.
    Univ Copenhagen, Dark Cosmol Ctr, Niels Bohr Inst, Juliane Maries Vej 30, DK-2100 Copenhagen, Denmark..
    Izzo, L.
    CSIC, IAA, Glorieta Astron S-N, E-18008 Granada, Spain..
    Kiss, L.
    Hungarian Acad Sci, Res Ctr Astron & Earth Sci, Konkoly Observ, Konkoly Thege Miklosut 15-17, H-1121 Budapest, Hungary..
    Kumar, P.
    Univ Texas Austin, Dept Astron, Austin, TX 78712 USA..
    Kuvvetli, I
    DTU Space Natl Space Inst Elektrovej, Bldg 327, DK-2800 Lyngby, Denmark..
    Lavagna, M.
    Politecn Milan, Via La Masa 1, I-20156 Milan, Italy..
    Li, T.
    Tsinghua Univ, Dept Engn Phys, Beijing, Peoples R China.;Tsinghua Univ, Ctr Astrophys, Beijing, Peoples R China..
    Longo, F.
    INFN Trieste, Via Valerio 2, Trieste, Italy.;Univ Trieste, Dept Phys, Via Valerio 2, Trieste, Italy..
    Lyutikov, M.
    Purdue Univ, Dept Phys, 525 Northwestern Ave, W Lafayette, IN 47907 USA.;McGill Univ, Dept Phys, 3600 Univ St, Montreal, PQ H3A 2T8, Canada.;McGill Univ, McGill Space Inst, 3600 Univ St, Montreal, PQ H3A 2T8, Canada..
    Maio, U.
    Leibniz Inst Astrophys, Sternwarte 16, D-14482 Potsdam, Germany.;Osserv Astron Trieste, INAF, Via G Tiepolo 11, I-34131 Trieste, Italy..
    Maiorano, E.
    IASF Bologna, INAF, Via Piero Gobetti 101, I-40129 Bologna, Italy..
    Malcovati, P.
    Univ Pavia, Dept Elect Comp & Biomed Engn, Pavia, Italy..
    Malesani, D.
    Univ Copenhagen, Dark Cosmol Ctr, Niels Bohr Inst, Juliane Maries Vej 30, DK-2100 Copenhagen, Denmark..
    Margutti, R.
    Northwestern Univ, CIERA, Evanston, IL 60208 USA.;Northwestern Univ, Dept Phys & Astrophys, Evanston, IL 60208 USA..
    Martin-Carrillo, A.
    Univ Coll Dublin, Sch Phys, Space Sci Grp, Dublin 4, Ireland..
    Masetti, N.
    IASF Bologna, INAF, Via Piero Gobetti 101, I-40129 Bologna, Italy.;Univ Andres Bello, Dept Ciencias Fis, Fernandez Concha 700, Santiago, Chile..
    McBreen, S.
    Univ Coll Dublin, Sch Phys, Stillorgan Rd, Dublin 4, Ireland..
    Mignani, R.
    Ist Astrofis Spaziale & Fis Cosm Milano, INAF, Via E Bassini 15, I-20133 Milan, Italy.;Univ Zielona Gora, Janusz Gil Inst Astron, Lubuska 2, PL-65265 Zielona Gora, Poland..
    Morgante, G.
    IASF Bologna, INAF, Via Piero Gobetti 101, I-40129 Bologna, Italy..
    Mundell, C.
    Univ Bath, Dept Phys, Bath BA2 7AY, Avon, England..
    Nargaard-Nielsen, H. U.
    DTU Space Natl Space Inst Elektrovej, Bldg 327, DK-2800 Lyngby, Denmark..
    Nicastro, L.
    Inst Astrofis Spaziale & Fis Cosm, INAF, Via Piero Gobetti 101, I-40129 Bologna, Italy..
    Palazzi, E.
    IASF Bologna, INAF, Via Piero Gobetti 101, I-40129 Bologna, Italy..
    Paltani, S.
    Univ Geneva, Dept Astron, Ch Ecogia 16, CH-1290 Versoix, Switzerland..
    Panessa, F.
    IAPS Roma, INAF, Via Fosso Cavaliere 100, I-00133 Rome, Italy..
    Pareschi, G.
    Osserv Astron Brera, INAF, Via E Bianchi 46, I-23807 Merate, LC, Italy..
    Pe'er, A.
    Univ Coll Cork, Dept Phys, Cork, Ireland..
    Penacchioni, A. , V
    Pian, E.
    Scuola Normale Super Pisa, Piazza Cavalieri 7, I-56126 Pisa, Italy..
    Piedipalumbo, E.
    Univ Napoli Federico II, Dipartimento Fis, Compl Univ Monte S Angelo, I-80126 Naples, Italy.;INFN, Sez Napoli, Univ Monte S Angelo,Edificio 6,Via Cinthia, I-80126 Naples, Italy..
    Piran, T.
    Hebrew Univ Jerusalem, Racah Inst Phys, IL-91904 Jerusalem, Israel..
    Rauw, G.
    Univ Liege, Quartier Agora, Allee 6 Aout 19c, B-4000 Liege, Belgium..
    Razzano, M.
    Univ Pisa, Dept Phys, I-56127 Pisa, Italy.;INFN Pisa, I-56127 Pisa, Italy..
    Read, A.
    Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England..
    Rezzolla, L.
    Goethe Univ Frankfurt, Inst Theoret Phys, Max von Laue Str 1, D-60438 Frankfurt, Germany.;Frankfurt Inst Adv Studies, Ruth Moufang Str 1, D-60438 Frankfurt, Germany..
    Romano, P.
    Osserv Astron Brera, INAF, Via E Bianchi 46, I-23807 Merate, Italy..
    Ruffini, R.
    ICRANet, Pzza Repubbl 10, I-65122 Pescara, Italy.;Sapienza Univ Roma, ICRA, Ple Aldo Moro 5, I-00185 Rome, Italy.;Sapienza Univ Roma, Dipartimento Fis, Ple Aldo Moro 5, I-00185 Rome, Italy..
    Savaglio, S.
    Univ Calabria, Phys Dept, Via P Bucci, I-87036 Arcavacata Di Rende, Italy..
    Sguera, V
    IASF Bologna, INAF, via P Gobetti 101, I-40129 Bologna, Italy..
    Schady, P.
    Max Planck Inst Extraterr Phys, Giessenbachstr 1, D-85748 Garching, Germany..
    Skidmore, W.
    Thirty Meter Telescope Int Observ, 100 W Walnut St,Suite 300, Pasadena, CA 91124 USA..
    Song, L.
    Chinese Acad Sci, Inst High Energy Phys, Key Lab Particle Astrophys, Beijing 100049, Peoples R China..
    Stanway, E.
    Univ Warwick, Dept Phys, Gibbet Hill Rd, Coventry CV4 7AL, W Midlands, England..
    Starling, R.
    Univ Leicester, Dept Phys & Astron, Univ Rd, Leicester LE1 7RH, Leics, England.;Univ Leicester, Leicester Inst Space & Earth Observat, Univ Rd, Leicester LE1 7RH, Leics, England..
    Topinka, M.
    Dublin Inst Adv Studies, Sch Cosm Phys, 31 Fitzwilliam Pl, Dublin 2, Ireland..
    Troja, E.
    Univ Maryland, Dept Astron, College Pk, MD 20742 USA.;NASA, Goddard Space Flight Ctr, 8800 Greenbelt Rd, Greenbelt, MD 20771 USA..
    van Putten, M.
    Sejong Univ, 98 Gunja Dong, Seoul 143747, South Korea..
    Vanzella, E.
    Osservatorio Astron Bologna, INAF, Via Ranzani 1, I-40127 Bologna, Italy..
    Vercellone, S.
    Osserv Astron Brera, INAF, Via E Bianchi 46, I-23807 Merate, Italy..
    Wilson-Hodge, C.
    NASA, Marshall Space Flight Ctr, Huntsville, AL USA..
    Yonetoku, D.
    Kanazawa Univ, Fac Math & Phys, Kanazawa, Ishikawa 9201192, Japan..
    Zampa, G.
    INFN Trieste, Via Valerio 2, Trieste, Italy..
    Zampa, N.
    INFN Trieste, Via Valerio 2, Trieste, Italy..
    Zhang, B.
    Univ Nevada, Dept Phys & Astron, Las Vegas, NV 89154 USA..
    Zhang, B. B.
    CSIC, IAA, POB 03004, E-18080 Granada, Spain..
    Zhang, S.
    Inst High Energy Phys, Beijing 100049, Peoples R China..
    Zhang, S-N
    Inst High Energy Phys, Beijing 100049, Peoples R China..
    Antonelli, A.
    ASDC, Via Politecn Snc, I-00133 Rome, Italy..
    Bianco, F.
    NYU, Ctr Cosmol & Particle Phys, 4 Washington Pl, New York, NY 10003 USA..
    Boci, S.
    Univ Tirana, Dept Phys, Tirana, Albania..
    Boer, M.
    Univ Cote dAzur, Observ Cote dAzur, ARTEMIS, CNRS UMR 5270,CS 34229, Blvd Observ, F-06304 Nice 04, France..
    Botticella, M. T.
    Capodimonte Astron Observ Naples, INAF, Via Moiariello 16, I-80131 Naples, Italy..
    Boulade, O.
    Univ Paris Saclay, IRFU, CEA, Dept Astrophys, F-91191 Gif Sur Yvette, France..
    Butler, C.
    IASF Bologna, INAF, via P Gobetti 101, I-40129 Bologna, Italy..
    Campana, S.
    Osserv Astron Brera, INAF, Via E Bianchi 46, I-23807 Merate, LC, Italy..
    Capitanio, F.
    IAPS Roma, INAF, Via Fosso Cavaliere 100, I-00133 Rome, Italy..
    Celotti, A.
    Osserv Astron Brera, INAF, Via Bianchi 46, I-23807 Merate, LC, Italy.;SISSA, Via Bonomea 265, I-34136 Trieste, Italy.;INFN, Sez Trieste, Via Valerio 2, I-34127 Trieste, Italy..
    Chen, Y.
    Inst High Energy Phys, Beijing 100049, Peoples R China..
    Colpi, M.
    Univ Milano Bicocca, Dipartimento Fis G Occhialini, Piazza Sci 3, I-20126 Milan, Italy.;INFN, Sez Milano Bicocca, Piazza Sci 3, I-20126 Milan, Italy..
    Comastri, A.
    Osservatorio Astron Bologna, INAF, Via Piero Gobetti 93-3, I-40129 Bologna, Italy..
    Cuby, J-G
    LAM, F-13388 Marseille, France..
    Dadina, M.
    IASF Bologna, INAF, via P Gobetti 101, I-40129 Bologna, Italy..
    De Luca, A.
    Ist Astrofis Spaziale & Fis Cosm Milano, INAF, Via E Bassini 15, I-20133 Milan, Italy..
    Dong, Y-W
    Inst High Energy Phys, Beijing 100049, Peoples R China..
    Ettori, S.
    INFN, Sez Bologna, Viale Berti Pichat 6-2, I-40127 Bologna, Italy.;Osservatorio Astron Bologna, INAF, Via Piero Gobetti 93-3, I-40129 Bologna, Italy..
    Gandhi, P.
    Univ Southampton, Dept Phys & Astron, Southampton SO17 1BJ, Hants, England..
    Geza, E.
    Hungarian Acad Sci, Wigner Res Ctr Phys, POB 49, H-1525 Budapest, Hungary..
    Greiner, J.
    Max Planck Inst Astrophys, Karl Schwarzschild Str 1, D-85741 Garching, Germany..
    Guiriec, S.
    Univ Maryland, Dept Astron, College Pk, MD 20742 USA.;George Washington Univ, Dept Phys, 725 21st St NW, Washington, DC 20052 USA.;NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.;CRESST, Greenbelt, MD 20771 USA..
    Harms, J.
    Univ Urbino Carlo Bo, I-61029 Urbino, Italy..
    Hernanz, M.
    CSIC, Inst Space Sci IEEC, Carrer Can Magrans S-N, E-08193 Barcelona, Spain..
    Hornstrup, A.
    DTU Space Natl Space Inst Elektrovej, Bldg 327, DK-2800 Lyngby, Denmark..
    Hutchinson, I
    Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England..
    Israel, G.
    Osserv Astron Roma, INAF, Via Frascati 33, I-00040 Monte Porzio Catone, Italy..
    Jonker, P.
    SRON, Netherlands Inst Space Res, Sorbonnelaan 2, NL-3584 CA Utrecht, Netherlands.;Radboud Univ Nijmegen, Dept Astrophys, IMAPP, POB 9010, NL-6500 GL Nijmegen, Netherlands..
    Kaneko, Y.
    Sabanc Univ, Fac Engn & Nat Sci, TR-34956 Istanbul, Turkey..
    Kawai, N.
    Tokyo Inst Technol, Dept Phys, Meguro Ku, 2-12-1 Ookayama, Tokyo 1528551, Japan..
    Wiersema, K.
    Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England..
    Korpela, S.
    Univ Helsinki, Dept Phys, POB 48, FIN-00014 Helsinki, Finland..
    Lebrun, V
    LAM, F-13388 Marseille, France..
    Lu, F.
    Inst High Energy Phys, Beijing 100049, Peoples R China..
    MacFadyen, A.
    NYU, Ctr Cosmol & Particle Phys, New York, NY USA..
    Malaguti, G.
    IASF Bologna, INAF, Via Piero Gobetti 101, I-40129 Bologna, Italy..
    Maraschi, L.
    Osserv Astron Brera, INAF, Via E Bianchi 46, I-23807 Merate, LC, Italy..
    Melandri, A.
    Osserv Astron Brera, INAF, Via E Bianchi 36, I-23807 Merate, LC, Italy..
    Modjaz, M.
    NYU, Ctr Cosmol & Particle Phys, Dept Phys, 726 Broadway Off 1044, New York, NY 10003 USA..
    Morris, D.
    Etelman Observ, St Thomas, VI 00802 USA.;Univ Virgin Isl, Coll Sci & Math, St Thomas, VI 00802 USA..
    Omodei, N.
    Stanford Univ, Kavli Inst Particle Astrophys & Cosmol, Dept Phys, WW Hansen Expt Phys Lab, Stanford, CA 94305 USA.;Stanford Univ, SLAC Natl Accelerator Lab, Stanford, CA 94305 USA..
    Paizis, A.
    IASF Milano, INAF, Via E Bassini 15, I-20133 Milan, Italy..
    Pata, P.
    Czech Tech Univ, Fac Elect Engn, Dept Radioelect, Tech 2, Prague 16627 6, Czech Republic..
    Petrosian, V
    Stanford Univ, Kavli Inst Particle Astrophys & Cosmol, Dept Phys, WW Hansen Expt Phys Lab, Stanford, CA 94305 USA.;Stanford Univ, SLAC Natl Accelerator Lab, Stanford, CA 94305 USA..
    Rachevski, A.
    INFN, Sez Trieste, Via Valerio 2, I-34127 Trieste, Italy..
    Rhoads, J.
    Arizona State Univ, Sch Earth & Space Explorat, Tempe, AZ 85287 USA.;Goddard Space Flight Ctr, Astrophys Sci Div, 8800 Greenbelt Rd, Greenbelt, MD 20771 USA..
    Ryde, Felix
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik. Oskar Klein Ctr Cosmoparticle Phys, SE-10691 Stockholm, Sweden.
    Sabau-Graziati, L.
    INTA, Div Ciencias Espacio, Madrid, Spain..
    Shigehiro, N.
    RIKEN, ABBL, Wako, Saitama 3510198, Japan..
    Sims, M.
    Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England..
    Soomin, J.
    CSIC, IAA, Glorieta Astron S-N, E-18008 Granada, Spain..
    Szecsi, D.
    Univ Birmingham, Inst Gravitat Wave Astron, Birmingham B15 2TT, W Midlands, England.;Univ Birmingham, Sch Phys & Astron, Birmingham B15 2TT, W Midlands, England.;Czech Acad Sci, Astron Inst, Frivcova 298, Ondvrejov 25165, Czech Republic..
    Urata, Y.
    Natl Cent Univ, Inst Astron, Chungli 32054, Taiwan..
    Uslenghi, M.
    IASF Bologna, INAF, Via E Bassini 15, I-20133 Milan, Italy..
    Valenziano, L.
    IASF Bologna, INAF, Via Gobetti 101, Bologna, Italy..
    Vianello, G.
    Stanford Univ, SLAC Natl Accelerator Lab, Stanford, CA 94305 USA..
    Vojtech, S.
    Acad Sci Czech Republ, Astron Inst, Fricova 1, CZ-25165 Ondrejov, Czech Republic..
    Watson, D.
    Univ Copenhagen, Dark Cosmol Ctr, Niels Bohr Inst, Juliane Maries Vej 30, DK-2100 Copenhagen, Denmark..
    Zicha, J.
    Czech Tech Univ, Fac Mech Engn, Dept Instrumentat & Control Engn, Tech 4, Prague 16607 6, Czech Republic..
    The THESEUS space mission concept: science case, design and expected performances2018Ingår i: Advances in Space Research, ISSN 0273-1177, E-ISSN 1879-1948, Vol. 62, nr 1, s. 191-244Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    THESEUS is a space mission concept aimed at exploiting Gamma-Ray Bursts for investigating the early Universe and at providing a substantial advancement of multi-messenger and time-domain astrophysics. These goals will be achieved through a unique combination of instruments allowing GRB and X-ray transient detection over a broad field of view (more than 1 sr) with 0.5-1 arcmin localization, an energy band extending from several MeV down to 0.3 keV and high sensitivity to transient sources in the soft X-ray domain, as well as on-board prompt (few minutes) follow-up with a 0.7 m class IR telescope with both imaging and spectroscopic capabilities. THESEUS will be perfectly suited for addressing the main open issues in cosmology such as, e.g., star formation rate and metallicity evolution of the inter-stellar and intra-galactic medium up to redshift similar to 10, signatures of Pop III stars, sources and physics of re-ionization, and the faint end of the galaxy luminosity function. In addition, it will provide unprecedented capability to monitor the X-ray variable sky, thus detecting, localizing, and identifying the electromagnetic counterparts to sources of gravitational radiation, which may be routinely detected in the late '20s/early '30s by next generation facilities like aLIGO/ aVirgo, eLISA, KAGRA, and Einstein Telescope. THESEUS will also provide powerful synergies with the next generation of multi-wavelength observatories (e.g., LSST, ELT, SKA, CTA, ATHENA).

  • 309.
    Aminalragia-Giamini, Sigiava
    et al.
    Space Applicat & Res Consultancy SPARC, Athens 10551, Greece.;Natl & Kapodistrian Univ Athens NKUA, Dept Phys, Athens 15772, Greece..
    Raptis, Savvas
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Elektroteknik, Rymd- och plasmafysik.
    Anastasiadis, Anastasios
    Inst Astron Astrophys Space Applicat & Remote Sen, Natl Observ Athens, Athens 15236, Greece..
    Tsigkanos, Antonis
    Space Applicat & Res Consultancy SPARC, Athens 10551, Greece..
    Sandberg, Ingmar
    Space Applicat & Res Consultancy SPARC, Athens 10551, Greece..
    Papaioannou, Athanasios
    Inst Astron Astrophys Space Applicat & Remote Sen, Natl Observ Athens, Athens 15236, Greece..
    Papadimitriou, Constantinos
    Space Applicat & Res Consultancy SPARC, Athens 10551, Greece.;Natl & Kapodistrian Univ Athens NKUA, Dept Phys, Athens 15772, Greece..
    Jiggens, Piers
    European Space Agcy ESTEC ESA, European Res & Technol Ctr, NL-2200 AZ Noordwijk, Netherlands..
    Aran, Angels
    Univ Barcelona UB IEEC, Inst Ciencies Cosmos ICCUB, Dept Fis Quant & Astrofis, Barcelona 08028, Spain..
    Daglis, Ioannis A.
    Natl & Kapodistrian Univ Athens NKUA, Dept Phys, Athens 15772, Greece.;Hellen Space Ctr, Athens 15231, Greece..
    Solar Energetic Particle Event occurrence prediction using Solar Flare Soft X-ray measurements and Machine Learning2021Ingår i: Journal of Space Weather and Space Climate, E-ISSN 2115-7251, Vol. 11, artikel-id 59Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The prediction of the occurrence of Solar Energetic Particle (SEP) events has been investigated over many years, and multiple works have presented significant advances in this problem. The accurate and timely prediction of SEPs is of interest to the scientific community as well as mission designers, operators, and industrial partners due to the threat SEPs pose to satellites, spacecrafts, and crewed missions. In this work, we present a methodology for the prediction of SEPs from the soft X-rays of solar flares associated with SEPs that were measured in 1 AU. We use an expansive dataset covering 25 years of solar activity, 1988-2013, which includes thousands of flares and more than two hundred identified and catalogued SEPs. Neural networks are employed as the predictors in the model, providing probabilities for the occurrence or not of a SEP, which are converted to yes/no predictions. The neural networks are designed using current and state-of-the-art tools integrating recent advances in the machine learning field. The results of the methodology are extensively evaluated and validated using all the available data, and it is shown that we achieve very good levels of accuracy with correct SEP occurrence prediction higher than 85% and correct no-SEP predictions higher than 92%. Finally, we discuss further work towards potential improvements and the applicability of our model in real-life conditions.

  • 310. Anand, S.
    et al.
    Andreoni, I.
    Goldstein, D. A.
    Kasliwal, M. M.
    Ahumada, T.
    Barnes, J.
    Bloom, J. S.
    Bulla, Mattia
    Nordita SU.
    Bradley Cenko, S.
    Cooke, J.
    Coughlin, M. W.
    Nugent, P. E.
    Singer, L. P.
    DECam-GROWTH search for the faint and distant binary neutron star and neutron star-black hole mergers in O3a2021Ingår i: Revista Mexicana de Astronomia y Astrofisica: Serie de Conferencias, Universidad Nacional Autonoma de Mexico , 2021, Vol. 53, s. 91-99Konferensbidrag (Refereegranskat)
    Abstract [en]

    Synoptic searches for the optical counterpart to a binary neutron star (BNS) or neutron star-black hole (NSBH) merger can pose significant challenges towards the discovery of kilonovae and performing multi-messenger science. In this work, we describe the advantage of a global multi-telescope network towards this end, with a particular focus on the key and complementary role the Dark Energy Camera (DECam) plays in multi-facility follow-up. We describe the Global Relay of Observatories Watching Transients Happen (GROWTH) Target-of-Opportunity (ToO) Marshal, a common web application we built to ingest events, plan observations, search for transient candidates, and retrieve performance summary statistics for all of the telescopes in our network. Our infrastructure enabled us to conduct observations of two events during O3a, S190426c and S190510g. Furthermore, our analysis of deep DECam observations of S190814bv conducted by the DESGW team, and access to a variety of global follow-up facilities allowed us to place meaningful constraints on the parameters of the kilonova and the merging binary. We emphasize the importance of a global telescope network in conjunction with a power telescope like DECam in performing searches for the counterparts to gravitational-wave sources. 

  • 311.
    Anand, Shreya
    et al.
    CALTECH, Cahill Ctr Astrophys, Pasadena, CA 91125 USA..
    Sarin, Nikhil
    Nordita SU; Stockholm Univ, Oskar Klein Ctr, Dept Phys, AlbaNova, Stockholm, Sweden..
    Zhang, Chaoran
    Univ Wisconsin, Ctr Gravitat Cosmol & Astrophys, Milwaukee, WI 53201 USA..
    Collapsars as Sites of r-process Nucleosynthesis: Systematic Photometric Near-infrared Follow-up of Type Ic-BL Supernovae2024Ingår i: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 962, nr 1, s. 68-, artikel-id 68Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    One of the open questions following the discovery of GW170817 is whether neutron star (NS) mergers are the only astrophysical sites capable of producing r-process elements. Simulations have shown that 0.01-0.1 M(circle dot )of r-process material could be generated in the outflows originating from the accretion disk surrounding the rapidly rotating black hole that forms as a remnant to both NS mergers and collapsing massive stars associated with long-duration gamma-ray bursts (collapsars). The hallmark signature of r-process nucleosynthesis in the binary NS merger GW170817 was its long-lasting near-infrared (NIR) emission, thus motivating a systematic photometric study of the light curves of broad-lined stripped-envelope (Ic-BL) supernovae (SNe) associated with collapsars. We present the first systematic study of 25 SNe Ic-BL-including 18 observed with the Zwicky Transient Facility and 7 from the literature-in the optical/NIR bands to determine what quantity of r-process material, if any, is synthesized in these explosions. Using semi-analytic models designed to account for r-process production in SNe Ic-BL, we perform light curve fitting to derive constraints on the r-process mass for these SNe. We also perform independent light curve fits to models without the r-process. We find that the r-process-free models are a better fit to the light curves of the objects in our sample. Thus, we find no compelling evidence of r-process enrichment in any of our objects. Further high-cadence infrared photometric studies and nebular spectroscopic analysis would be sensitive to smaller quantities of r-process ejecta mass or indicate whether all collapsars are completely devoid of r-process nucleosynthesis.

  • 312.
    Andersson, B-G
    et al.
    Univ Space Res Assoc, NASA Ames Res Ctr, SOFIA Sci Ctr, MS N232-12, Moffett Field, CA 94035 USA..
    Lopez-Rodriguez, Enrique
    Univ Space Res Assoc, NASA Ames Res Ctr, SOFIA Sci Ctr, MS N232-12, Moffett Field, CA 94035 USA.;Stanford Univ, Kavli Inst Particle Astrophys & Cosmol KIPAC, Stanford, CA 94305 USA..
    Medan, Ilija
    Georgia State Univ, Dept Phys & Astron, Atlanta, GA 30302 USA..
    Soam, Archana
    Univ Space Res Assoc, NASA Ames Res Ctr, SOFIA Sci Ctr, MS N232-12, Moffett Field, CA 94035 USA.;Indian Inst Astrophys, 2 Block, Bengaluru 560034, Karnataka, India..
    Hoang, Thiem
    Korea Astron & Space Sci Inst, Daejeon 34055, South Korea.;Korea Univ Sci & Technol, 217 Gajeong Ro, Daejeon 34113, South Korea..
    Vaillancourt, John E.
    MIT, Lincoln Lab, 244 Wood St, Lexington, MA 02421 USA..
    Lazarian, Alex
    Univ Wisconsin, Dept Astron, 475 North Charter St, Madison, WI 53706 USA.;Univ Bernardo OHiggins, Ctr Invest Astron, Gen Gana 1760, Santiago 8370993, Chile..
    Sandin, Christer
    KTH, Centra, Nordic Institute for Theoretical Physics NORDITA. Stockholm Univ, Roslagstullsbacken 23, SE-10691 Stockholm, Sweden..
    Mattsson, Lars
    KTH, Centra, Nordic Institute for Theoretical Physics NORDITA. Stockholm Univ, Roslagstullsbacken 23, SE-10691 Stockholm, Sweden..
    Tahani, Mehrnoosh
    Natl Res Council Canada, Herzberg Astron & Astrophys Res Ctr, Dominion Radio Astrophys Observ, POB 248, Penticton, BC V2A 6J9, Canada..
    Grain Alignment in the Circumstellar Shell of IRC+10 degrees 2162022Ingår i: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 931, nr 2, s. 80-, artikel-id 80Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Dust-induced polarization in the interstellar medium (ISM) is due to asymmetric grains aligned with an external reference direction, usually the magnetic field. For both the leading alignment theories, the alignment of the grain's angular momentum with one of its principal axes and the coupling with the magnetic field requires the grain to be paramagnetic. Of the two main components of interstellar dust, silicates are paramagnetic, while carbon dust is diamagnetic. Hence, carbon grains are not expected to align in the ISM. To probe the physics of carbon grain alignment, we have acquired Stratospheric Observatory for Infrared Astronomy/Higch-resolution Airborne Wideband Camera-plus far-infrared photometry and polarimetry of the carbon-rich circumstellar envelope (CSE) of the asymptotic giant branch star IRC+10 degrees 216. The dust in such CSEs are fully carbonaceous and thus provide unique laboratories for probing carbon grain alignment. We find a centrosymmetric, radial, polarization pattern, where the polarization fraction is well correlated with the dust temperature. Together with estimates of a low fractional polarization from optical polarization of background stars, we interpret these results to be due to a second-order, direct radiative external alignment of grains without internal alignment. Our results indicate that (pure) carbon dust does not contribute significantly to the observed ISM polarization, consistent with the nondetection of polarization in the 3.4 mu m feature due to aliphatic CH bonds on the grain surface.

  • 313.
    Andersson, Karl E.
    et al.
    KTH, Tidigare Institutioner (före 2005), Fysik.
    Madejski, G M
    Complex structure of galaxy cluster A1689: Evidence for a merger from X-ray data?2004Ingår i: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 607, nr 1, s. 190-201Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A1689 is a galaxy cluster at z = 0.183 for which previous measurements of its mass by using various techniques gave discrepant results. We present a new detailed measurement of the mass with the data based on X-ray observations with the European Photon Imaging Camera aboard the XMM-Newton Observatory, determined by using an unparameterized deprojection technique. Fitting the total mass profile to a Navarro-Frenk-White model yields halo concentration c = 7.2(-2.4)(+1.6) and r(200) = 1.13 +/- 0.21 h(-1) Mpc, corresponding to a mass that is less than half of that found from gravitational lensing. Adding to the evidence of substructure from optical observations, X-ray analysis shows a highly asymmetric temperature profile and a nonuniform redshift distribution, implying large-scale relative motion of the gas. A lower than expected gas mass fraction f(gas) = 0.072 +/- 0: 008 (for a flat LambdaCDM cosmology) suggests a complex spatial and/or dynamical structure. We also find no sign of any additional absorbing component previously reported on the basis of the Chandra data, confirming the XMM-Newton low-energy response by using data from ROSAT.

  • 314. Andersson, V.
    et al.
    Chen, P.
    Kamae, T.
    Madejski, G.
    Mizuno, T.
    Ng, J. S. T.
    Suhonen, M.
    Tajima, H.
    Thurston, T.
    Bogaert, G.
    Fukazawa, Y.
    Saito, Y.
    Takahashi, T.
    Barbier, L.
    Bloser, P.
    Cline, T.
    Harding, A.
    Hunter, S.
    Krizmanic, J.
    Mitchell, J.
    Streitmatter, R.
    Fernholz, R.
    Groth, E.
    Marlow, D.
    Carlson, Per
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Klamra, Wlodzimierz
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Pearce, Mark
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Bjornsson, C. -I
    Fransson, C.
    Larsson, S.
    Ryde, Felix
    Stockholm University.
    Arimoto, M.
    Ikagawa, T.
    Kanai, Y.
    Kataoka, J.
    Kawai, N.
    Yatsu, Y.
    Gunji, S.
    Sakurai, H.
    Yamashita, Y.
    Large-Area Balloon-Borne Polarized Gamma Ray Observer (PoGO)2005Ingår i: Proceedings of the 22nd Texas Symposium on Relativistic Astrophysics at Stanford, 2005, s. 736-743Konferensbidrag (Refereegranskat)
    Abstract [en]

    We are developing a new balloon-borne instrument (PoGO), to measure polarization of soft gamma rays (30-200 keV) using asymmetry in azimuth angle distribution of Compton scattering. PoGO is designed to detect 10 % polarization in 100mCrab sources in a 6-8 hour observation and bring a new dimension to studies on gamma ray emission/transportation mechanism in pulsars, AGNs, black hole binaries, and neutron star surface. The concept is an adaptation to polarization measurements of well-type phoswich counter consisting of a fast plastic scintillator (the detection part), a slow plastic scintillator (the active collimator) and a BGO scintillator (the bottom anti-counter). PoGO consists of close-packed array of 217 hexagonal well-type phoswich counters and has a narrow field-of-view (~ 5 deg2) to reduce possible source confusion. A prototype instrument has been tested in the polarized soft gamma-ray beams at Advanced Photon Source (ANL) and at Photon Factory (KEK). On the results, the polarization dependence of EGS4 has been validated and that of Geant4 has been corrected.

  • 315. Andre, M.
    et al.
    Behlke, R.
    Wahlund, J. E.
    Vaivads, A.
    Eriksson, A. I.
    Tjulin, A.
    Carozzi, T. D.
    Cully, C.
    Gustafsson, G.
    Sundkvist, D.
    Khotyaintsev, Y.
    Cornilleau-Wehrlin, N.
    Rezeau, L.
    Maksimovic, M.
    Lucek, E.
    Balogh, A.
    Dunlop, M.
    Lindqvist, Per-Arne
    KTH, Tidigare Institutioner (före 2005), Alfvénlaboratoriet.
    Mozer, F.
    Pedersen, A.
    Fazakerley, A.
    Multi-spacecraft observations of broadband waves near the lower hybrid frequency at the Earthward edge of the magnetopause2001Ingår i: Annales Geophysicae, ISSN 0992-7689, E-ISSN 1432-0576, Vol. 19, nr 12-okt, s. 1471-1481Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Broadband waves around the lower hybrid frequency (around 10 Hz) near the magnetopause are studied, using the four Cluster satellites. These waves are common at the Earthward edge of the boundary layer, consistent with earlier observations, and can have amplitudes at least up to 5 mV/m. These waves are similar on all four Cluster satellites, i.e. they are likely to be distributed over large areas of the boundary. The strongest electric fields occur during a few seconds, i.e. over distances of a few hundred km in the frame of the moving magnetopause, a scale length comparable to the ion gyroradius. The strongest magnetic oscillations in the same frequency range are typically found in the boundary layer, and across the magnetopause. During an event studied in detail, the magnetopause velocity is consistent with a large-scale depression wave, i.e. an inward bulge of magnetosheath plasma, moving tailward along the nominal magnetopause boundary. Preliminary investigations indicate that a rather flat front side of the large-scale wave is associated with a rather static small-scale electric field, while a more turbulent backside of the large-scale wave is associated with small-scale time varying electric field wave packets.

  • 316. Andreoni, Igor
    et al.
    Bulla, Mattia
    KTH, Centra, Nordic Institute for Theoretical Physics NORDITA. Stockholm Univ, Roslagstullsbacken 23, SE-10691 Stockholm, Sweden..
    Yao, Yuhan
    Constraining the Kilonova Rate with Zwicky Transient Facility Searches Independent of Gravitational Wave and Short Gamma-Ray Burst Triggers2020Ingår i: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 904, nr 2, artikel-id 155Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The first binary neutron star merger, GW170817, was accompanied by a radioactivity-powered optical/infrared transient called a kilonova. To date, no compelling kilonova has been found in all-sky optical surveys, independently of short gamma-ray burst and gravitational-wave triggers. In this work, we searched the first 23 months of the Zwicky Transient Facility (ZTF) data stream for candidate kilonovae in the form of rapidly evolving transients. We combined ZTF alert queries with forced point-spread-function photometry and nightly flux stacking to increase our sensitivity to faint and fast transients. Automatic queries yielded >11,200 candidates, 24 of which passed quality checks and selection criteria based on a grid of kilonova models tailored for both binary neutron star and neutron star-black hole mergers. None of the candidates in our sample was deemed a possible kilonova after thorough vetting. The sources that passed our selection criteria are dominated by Galactic cataclysmic variables. We identified two fast transients at high Galactic latitude, one of which is the confirmed afterglow of long-duration GRB.190106A, the other is a possible cosmological afterglow. Using a survey simulation code, we constrained the kilonova rate for a range of models including top-hat, linearly decaying light curves, and synthetic light curves obtained with radiative transfer simulations. For prototypical GW170817-like kilonovae, we constrain the rate to be R < 1775 Gpc(-3) yr(-1) (95% confidence). By assuming a population of kilonovae with the same geometry and composition of GW170817 observed under a uniform viewing angle distribution, we obtained a constraint on the rate of R.<.4029 Gpc(-3) yr(-1).

  • 317.
    Andreoni, Igor
    et al.
    CALTECH, 1200 East Calif Blvd,MC 249-17, Pasadena, CA 91125 USA..
    Bulla, Mattia
    KTH, Centra, Nordic Institute for Theoretical Physics NORDITA. Stockholm Univ, Roslagstullsbacken 23, SE-10691 Stockholm, Sweden.;Stockholm Univ, Dept Phys, Oskar Klein Ctr, AlbaNova, SE-10691 Stockholm, Sweden..
    Zhang, Keming
    Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA..
    GROWTH on S190814bv: Deep Synoptic Limits on the Optical/Near-infrared Counterpart to a Neutron Star-Black Hole Merger2020Ingår i: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 890, nr 2, artikel-id 131Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    On 2019 August 14, the Advanced LIGO and Virgo interferometers detected the high-significance gravitational wave (GW) signal S190814bv. The GW data indicated that the event resulted from a neutron star-black hole (NSBH) merger, or potentially a low-mass binary BH merger. Due to the low false-alarm rate and the precise localization (23 deg(2) at 90%), S190814bv presented the community with the best opportunity yet to directly observe an optical/near-infrared counterpart to an NSBH merger. To search for potential counterparts, the GROWTH Collaboration performed real-time image subtraction on six nights of public Dark Energy Camera images acquired in the 3 weeks following the merger, covering >98% of the localization probability. Using a worldwide network of follow-up facilities, we systematically undertook spectroscopy and imaging of optical counterpart candidates. Combining these data with a photometric redshift catalog, we ruled out each candidate as the counterpart to S190814bv and placed deep, uniform limits on the optical emission associated with S190814bv. For the nearest consistent GW distance, radiative transfer simulations of NSBH mergers constrain the ejecta mass of S190814bv to be M-ej < 0.04 M-circle dot at polar viewing angles, or M-ej < 0.03 Me if the opacity is kappa < 2 cm(2)g(-1). Assuming a tidal deformability for the NS at the high end of the range compatible with GW170817 results, our limits would constrain the BH spin component aligned with the orbital momentum to be chi < 0.7 for mass ratios Q < 6, with weaker constraints for more compact NSs.

  • 318. Andrievsky, Alexander
    et al.
    Brandenburg, Axel
    KTH, Centra, Nordic Institute for Theoretical Physics NORDITA. Department of Astronomy, Stockholm University, AlbaNova University Center, Stockholm, Sweden.
    Noullez, Alain
    Zheligovsky, Vladislav
    Negative magnetic eddy diffusivities from the test-field method and multiscale stability theory2015Ingår i: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 811, nr 2, artikel-id 135Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The generation of a large-scale magnetic field in the kinematic regime in the absence of an alpha-effect is investigated by following two different approaches: the test-field method and the multiscale stability theory relying on the homogenization technique. Our computations of the magnetic eddy diffusivity tensor of the parity-invariant flow IV of G. O. Roberts and the modified Taylor-Green flow confirm the findings of previous studies. and also explain some of their apparent contradictions. The two flows have large symmetry groups; this is used to considerably simplify the eddy diffusivity tensor. Finally, a new analytic result is presented: upon expressing the eddy diffusivity tensor in terms of solutions to auxiliary problems for the adjoint operator, we derive relations between the magnetic eddy diffusivity tensors that arise for mutually reverse small-scale flows v(x) and - v(x).

  • 319. Antipin, Oleg
    et al.
    Mojaza, Matin
    KTH, Centra, Nordic Institute for Theoretical Physics NORDITA.
    Sannino, Francesco
    Minimal Coleman-Weinberg theory explains the diphoton excess2016Ingår i: PHYSICAL REVIEW D, ISSN 2470-0010, Vol. 93, nr 11, artikel-id 115007Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We replace the standard Higgs-mechanism by the Coleman-Weinberg mechanism, and investigate its viability through the addition of a new scalar field. As we showed in a previous study, minimal models of this type can alleviate the hierarchy problem of the Higgs-mass through the so-called Veltman conditions. We here extend the previous analysis by taking into account the important difference between running mass and pole mass of the scalar states. We then investigate whether these theories can account for the 750 GeV excess in diphotons observed by the LHC collaborations. New QCD-colored fermions in the TeV mass range coupled to the new scalar state are needed to describe the excess. We further show, by explicit computation of the running of the couplings, that the model is under perturbative control till just above the masses of the heaviest states of the theory. We further suggest related testable signatures and thereby show that the LHC experiments can test these models.

  • 320.
    Aoude, Rafael
    et al.
    Centre for Cosmology, Particle Physics and Phenomenology (CP3), Université catholique de Louvain, 1348 Louvain-la-Neuve, Belgium.
    Haddad, Kays
    Nordita SU; Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, Sweden, Box 516.
    Helset, Andreas
    Walter Burke Institute for Theoretical Physics, California Institute of Technology, Pasadena, California 91125, USA.
    Classical gravitational scattering amplitude at O (G2 S1∞ S2∞)2023Ingår i: Physical Review D: covering particles, fields, gravitation, and cosmology, ISSN 2470-0010, E-ISSN 2470-0029, Vol. 108, nr 2, artikel-id 024050Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We calculate the scattering amplitude of two rotating objects with the linear-in-curvature spin-induced multipoles of Kerr black holes at O(G2) and all orders in the spins of both objects. This is done including the complete set of contact terms potentially relevant to Kerr-black-hole scattering at O(G2). As such, Kerr black holes should be described by this scattering amplitude for a specific choice of values for the contact-term coefficients. The inclusion of all potential contact terms means this amplitude allows for a comprehensive search for structures emerging for certain values of the coefficients, and hence special properties that might be exhibited by Kerr-black-hole scattering. Our result can also act as a template for comparison for future computations of classical gravitational high-spin scattering.

  • 321.
    Aoude, Rafael
    et al.
    Catholic Univ Louvain, Ctr Cosmol Particle Phys & Phenomenol CP3, B-1348 Louvain La Neuve, Belgium..
    Haddad, Kays
    Nordita SU; Uppsala Univ, Dept Phys & Astron, Box 516, S-75120 Uppsala, Sweden..
    Helset, Andreas
    CALTECH, Walter Burke Inst Theoret Phys, Pasadena, CA 91125 USA..
    Classical Gravitational Spinning-Spinless Scattering at O(G(2)S(infinity))2022Ingår i: Physical Review Letters, ISSN 0031-9007, E-ISSN 1079-7114, Vol. 129, nr 14, artikel-id 141102Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Making use of the recently derived, all-spin, opposite-helicity Compton amplitude, we calculate the classical gravitational scattering amplitude for one spinning and one spinless object at O(G(2)) and all orders in spin. By construction, this amplitude exhibits the spin structure that has been conjectured to describe Kerr black holes. This spin structure alone is not enough to fix all deformations of the Compton amplitude by contact terms, but when combined with considerations of the ultrarelativistic limit we can uniquely assign values to the parameters remaining in the even-in-spin sector. Once these parameters are determined, much of the spin dependence of the amplitude resums into hypergeometric functions. Finally, we derive the eikonal phase for aligned-angular-momentum scattering.

  • 322.
    Aoyagi, M.
    et al.
    Osaka University, Department of Earth and Space Science, Graduate School of Science, and Project Research Center for Fundamental Sciences, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan, 1-1 Machikaneyama-cho, Toyonaka.
    Bose, R. G.
    Physics Department, Washington University in St. Louis, 1 Brookings Drive, CB 1105, St. Louis, MO 63130, USA, 1 Brookings Drive, CB 1105; McDonnell Center for the Space Sciences, Washington University in St. Louis, 1 Brookings Drive, CB 1105, St. Louis, MO 63130, USA, 1 Brookings Drive, CB 1105.
    Chun, S.
    Physics Department, Washington University in St. Louis, 1 Brookings Drive, CB 1105, St. Louis, MO 63130, USA, 1 Brookings Drive, CB 1105; McDonnell Center for the Space Sciences, Washington University in St. Louis, 1 Brookings Drive, CB 1105, St. Louis, MO 63130, USA, 1 Brookings Drive, CB 1105.
    Gau, E.
    Physics Department, Washington University in St. Louis, 1 Brookings Drive, CB 1105, St. Louis, MO 63130, USA, 1 Brookings Drive, CB 1105; McDonnell Center for the Space Sciences, Washington University in St. Louis, 1 Brookings Drive, CB 1105, St. Louis, MO 63130, USA, 1 Brookings Drive, CB 1105.
    Hu, K.
    Physics Department, Washington University in St. Louis, 1 Brookings Drive, CB 1105, St. Louis, MO 63130, USA, 1 Brookings Drive, CB 1105; McDonnell Center for the Space Sciences, Washington University in St. Louis, 1 Brookings Drive, CB 1105, St. Louis, MO 63130, USA, 1 Brookings Drive, CB 1105.
    Ishiwata, K.
    Osaka University, Department of Earth and Space Science, Graduate School of Science, and Project Research Center for Fundamental Sciences, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan, 1-1 Machikaneyama-cho, Toyonaka.
    Iyer, Nirmal
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Kislat, F.
    University of New Hampshire, Department of Physics and Astronomy, and Space Science Center, Morse Hall, 8 College Road, Durham, NH 03824, USA, 8 College Road.
    Kiss, Mózsi
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Klepper, Kassi
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Krawczynski, H.
    Physics Department, Washington University in St. Louis, 1 Brookings Drive, CB 1105, St. Louis, MO 63130, USA, 1 Brookings Drive, CB 1105; McDonnell Center for the Space Sciences, Washington University in St. Louis, 1 Brookings Drive, CB 1105, St. Louis, MO 63130, USA, 1 Brookings Drive, CB 1105.
    Lisalda, L.
    Physics Department, Washington University in St. Louis, 1 Brookings Drive, CB 1105, St. Louis, MO 63130, USA, 1 Brookings Drive, CB 1105; McDonnell Center for the Space Sciences, Washington University in St. Louis, 1 Brookings Drive, CB 1105, St. Louis, MO 63130, USA, 1 Brookings Drive, CB 1105.
    Maeda, Y.
    Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Sagamihara, Kanagawa 229-8510, Japan, 3-1-1 Yoshinodai, Sagamihara.
    af Malmborg, Filip
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Matsumoto, H.
    Osaka University, Department of Earth and Space Science, Graduate School of Science, and Project Research Center for Fundamental Sciences, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan, 1-1 Machikaneyama-cho, Toyonaka; Forefront Research Center, Osaka University, Japan.
    Miyamoto, A.
    Department of Physics, Tokyo Metropolitan University, 1-1 Minami-Osawa, Hachioji, Tokyo 192-0397, Japan, 1-1 Minami-Osawa, Hachioji.
    Miyazawa, T.
    Okinawa Institute of Science and Technology Graduate University 1919-1 Tancha, Onna-son, Kunigami-gun Okinawa, Japan 904-0495, 1919-1 Tancha, Onna-son, Kunigami-gun Okinawa.
    Pearce, Mark
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Rauch, B. F.
    Physics Department, Washington University in St. Louis, 1 Brookings Drive, CB 1105, St. Louis, MO 63130, USA, 1 Brookings Drive, CB 1105; McDonnell Center for the Space Sciences, Washington University in St. Louis, 1 Brookings Drive, CB 1105, St. Louis, MO 63130, USA, 1 Brookings Drive, CB 1105.
    Rodriguez Cavero, N.
    Physics Department, Washington University in St. Louis, 1 Brookings Drive, CB 1105, St. Louis, MO 63130, USA, 1 Brookings Drive, CB 1105; McDonnell Center for the Space Sciences, Washington University in St. Louis, 1 Brookings Drive, CB 1105, St. Louis, MO 63130, USA, 1 Brookings Drive, CB 1105.
    Spooner, S.
    University of New Hampshire, Department of Physics and Astronomy, and Space Science Center, Morse Hall, 8 College Road, Durham, NH 03824, USA, 8 College Road.
    Takahashi, H.
    Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan, 1-3-1 Kagamiyama, Higashi-Hiroshima.
    Uchida, Y.
    Tokyo University of Science 2641 Yamazaki, Noda, Chiba 278-8510, Japan, 2641 Yamazaki, Noda.
    West, A. T.
    Physics Department, Washington University in St. Louis, 1 Brookings Drive, CB 1105, St. Louis, MO 63130, USA, 1 Brookings Drive, CB 1105; McDonnell Center for the Space Sciences, Washington University in St. Louis, 1 Brookings Drive, CB 1105, St. Louis, MO 63130, USA, 1 Brookings Drive, CB 1105; Currently at University of Arizona, Department of Astronomy, Steward Observatory, 933 North Cherry Avenue, Tucson, AZ 85721-0065, USA, 933 North Cherry Avenue.
    Wimalasena, K.
    University of New Hampshire, Department of Physics and Astronomy, and Space Science Center, Morse Hall, 8 College Road, Durham, NH 03824, USA, 8 College Road.
    Yoshimoto, M.
    Osaka University, Department of Earth and Space Science, Graduate School of Science, and Project Research Center for Fundamental Sciences, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan, 1-1 Machikaneyama-cho, Toyonaka.
    Systematic effects on a Compton polarimeter at the focus of an X-ray mirror2024Ingår i: Astroparticle physics, ISSN 0927-6505, E-ISSN 1873-2852, Vol. 158, artikel-id 102944Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    XL-Calibur is a balloon-borne Compton polarimeter for X-rays in the ∼15–80 keV range. Using an X-ray mirror with a 12 m focal length for collecting photons onto a beryllium scattering rod surrounded by CZT detectors, a minimum-detectable polarization as low as ∼3% is expected during a 24-hour on-target observation of a 1 Crab source at 45° elevation. Systematic effects alter the reconstructed polarization as the mirror focal spot moves across the beryllium scatterer, due to pointing offsets, mechanical misalignment or deformation of the carbon-fiber truss supporting the mirror and the polarimeter. Unaddressed, this can give rise to a spurious polarization signal for an unpolarized flux, or a change in reconstructed polarization fraction and angle for a polarized flux. Using bench-marked Monte-Carlo simulations and an accurate mirror point-spread function characterized at synchrotron beam-lines, systematic effects are quantified, and mitigation strategies discussed. By recalculating the scattering site for a shifted beam, systematic errors can be reduced from several tens of percent to the few-percent level for any shift within the scattering element. The treatment of these systematic effects will be important for any polarimetric instrument where a focused X-ray beam is impinging on a scattering element surrounded by counting detectors.

  • 323. Apostolakis, A
    et al.
    Aslanides, E.
    -.
    Backenstoss, G.
    -.
    Bargassa, P.
    -.
    Behnke, O.
    -.
    Benelli, A.
    -.
    Bertin, V.
    -.
    Blanc, F.
    -.
    Bloch, P.
    -.
    Carlson, P.
    KTH, Skolan för teknikvetenskap (SCI).
    Danielsson, Mats
    KTH, Tidigare Institutioner (före 2005), Fysik.
    A determination of the CP violation parameter η+- from the decay of strangeness-tagged neutral kaons1999Ingår i: Physics Letters B, ISSN 0370-2693, E-ISSN 1873-2445, Vol. 458, nr 4, s. 545-552Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    LEAR offered unique opportunities to study the symmetries which exist between matter and antimatter. At variance with other approaches at this facility, CPLEAR was an experiment devoted to the study of CP, T and CPT symmetries in the neutral-kaon system. A variety of measurements allowed us to determine with high precision the parameters which describe the time evolution of the neutral kaons and their antiparticles, including decay amplitudes, and the related symmetry properties. Limits concerning quantum-mechanical predictions (EPR, coherence of the wave function) or the equivalence principle of general relativity have been obtained. An account of the main features of the experiment and its performances is given here, together with the results achieved.

  • 324.
    Arendt, Richard G.
    et al.
    Univ Maryland Baltimore Cty, Ctr Space Sci & Technol, Baltimore, MD 21250 USA.;Code 665,8800 Greenbelt Rd, Greenbelt, MD 20771 USA.;NASA GSFC, Ctr Res & Explorat Space Sci & Technol, Greenbelt, MD 20771 USA..
    Boyer, Martha L.
    Space Telescope Sci Inst, 3700 San Martin Dr, Baltimore, MD 21218 USA..
    Dwek, Eli
    Code 665,8800 Greenbelt Rd, Greenbelt, MD 20771 USA..
    Matsuura, Mikako
    Cardiff Univ, Sch Phys & Astron, Queens Bldg, Cardiff CF24 3AA, Wales..
    Ravi, Aravind P.
    Univ Texas Arlington, Dept Phys, Box 19059, Arlington, TX 76019 USA..
    Rest, Armin
    Space Telescope Sci Inst, 3700 San Martin Dr, Baltimore, MD 21218 USA.;Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA..
    Chevalier, Roger
    Univ Virginia, Dept Astron, POB 400325, Charlottesville, VA 22904 USA..
    Cigan, Phil
    US Naval Observ, 3450 Massachusetts Ave NW, Washington, DC 20392 USA..
    De Looze, Ilse
    Univ Ghent, Sterrenkundig Observ, Krijgslaan 281-S9, B-9000 Ghent, Belgium..
    De Marchi, Guido
    European Space Technol Ctr, Keplerlaan 1, NL-2200 AG Noordwijk, Netherlands..
    Fransson, Claes
    Stockholm Univ, Oskar Klein Ctr, Dept Astron, AlbaNova, SE-10691 Stockholm, Sweden..
    Gall, Christa
    Univ Copenhagen, Niels Bohr Inst, DARK, Jagtvej 128, DK-2200 Copenhagen, Denmark..
    Gehrz, R. D.
    Univ Minnesota, Minnesota Inst Astrophys, 116 Church St SE, Minneapolis, MN 55455 USA..
    Gomez, Haley L.
    Cardiff Univ, Sch Phys & Astron, Queens Bldg, Cardiff CF24 3AA, Wales..
    Kangas, Tuomas
    Univ Turku, Finnish Ctr Astron ESO FINCA, FI-20014 Turku, Finland.;Univ Turku, Dept Phys & Astron, Tuorla Observ, FI-20014 Turku, Finland..
    Kirchschlager, Florian
    Univ Ghent, Sterrenkundig Observ, Krijgslaan 281-S9, B-9000 Ghent, Belgium..
    Kirshner, Robert P.
    TMT Int Observ, 100 W Walnut St, Pasadena, CA 91124 USA..
    Larsson, Josefin
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Lundqvist, Peter
    Stockholm Univ, Albanova Univ Ctr, Oskar Klein Ctr, Dept Astron, SE-10691 Stockholm, Sweden..
    Milisavljevic, Dan
    Purdue Univ, Dept Phys & Astron, W Lafayette, IN 47907 USA..
    Park, Sangwook
    Univ Texas Arlington, Dept Phys, Box 19059, Arlington, TX 76019 USA..
    Smith, Nathan
    Univ Arizona, Steward Observ, 933 N Cherry Ave, Tucson, AZ 85721 USA..
    Spyromilio, Jason
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Garching, Germany..
    Temim, Tea
    Princeton Univ, Dept Astrophys Sci, Princeton, NJ 08544 USA..
    Wang, Lifan
    Texas A&M Univ, Phys & Astron, College Stn, TX 77843 USA.;Texas A&M Univ, Mitchell Inst Fundamental Phys & Astron, College Stn, TX 77843 USA..
    Wheeler, J. Craig
    Univ Texas Austin, Dept Astron, Austin, TX 78712 USA..
    Woodward, Charles E.
    Univ Minnesota, Minnesota Inst Astrophys, 116 Church St SE, Minneapolis, MN 55455 USA..
    JWST NIRCam Observations of SN 1987A: Spitzer Comparison and Spectral Decomposition2023Ingår i: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 959, nr 2, artikel-id 95Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    JWST Near Infrared Camera (NIRCam) observations at 1.5-4.5 mu m have provided broadband and narrowband imaging of the evolving remnant of SN 1987A with unparalleled sensitivity and spatial resolution. Comparing with previous marginally spatially resolved Spitzer Infrared Array Camera (IRAC) observations from 2004 to 2019 confirms that the emission arises from the circumstellar equatorial ring (ER), and the current brightness at 3.6 and 4.5 mu m was accurately predicted by extrapolation of the declining brightness tracked by IRAC. Despite the regular light curve, the NIRCam observations clearly reveal that much of this emission is from a newly developing outer portion of the ER. Spots in the outer ER tend to lie at position angles in between the well-known ER hotspots. We show that the bulk of the emission in the field can be represented by five standard spectral energy distributions, each with a distinct origin and spatial distribution. This spectral decomposition provides a powerful technique for distinguishing overlapping emission from the circumstellar medium and the supernova ejecta, excited by the forward and reverse shocks, respectively.

  • 325. Arimoto, Makoto
    et al.
    Asano, Katsuaki
    Ohno, Masanori
    Veres, Peter
    Axelsson, Magnus
    KTH, Skolan för teknikvetenskap (SCI), Fysik. Tokyo Metropolitan University, Japan.
    Bissaldi, Elisabetta
    Tachibana, Yutaro
    Kawai, Nobuyuki
    HIGH-ENERGY NON-THERMAL AND THERMAL EMISSION FROM GRB 141207A DETECTED BY FERMI2016Ingår i: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 833, nr 2, artikel-id 139Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A bright long gamma-ray burst GRB 141207A was observed by the Fermi Gamma-ray Space Telescope and detected by both instruments onboard. The observations show that the spectrum in the prompt phase is not well described by the canonical empirical Band function alone, and that an additional power-law component is needed. In the early phase of the prompt emission, a modified blackbody with a hard low-energy photon index (alpha = +0.2 to +0.4) is detected, which suggests a photospheric origin. In a finely time-resolved analysis, the spectra are also well fitted by the modified blackbody combined with a power-law function. We discuss the physical parameters of the photosphere such as the bulk Lorentz factor of the relativistic flow and the radius. We also discuss the physical origin of the extra power-law component observed during the prompt phase in the context of different models such as leptonic and hadronic scenarios in the internal shock regime and synchrotron emission in the external forward shock. In the afterglow phase, the temporal and spectral behaviors of the temporally extended high-energy emission and the fading X-ray emission detected by the X-Ray Telescope on-board Swift are consistent with synchrotron emission in a radiative external forward shock.

  • 326.
    Arimoto, Makoto
    et al.
    Kanazawa Univ, Inst Sci & Engn, Fac Math & Phys, Kanazawa, Ishikawa 9201192, Japan..
    Asano, Katsuaki
    Univ Tokyo, Inst Cosm Ray Res, 5-1-5 Kashiwanoha, Kashiwa, Chiba 2778582, Japan..
    Tachibana, Yutaro
    Tokyo Inst Technol, Meguro Ku, 2-12-1 Ookayama, Tokyo 1528551, Japan..
    Axelsson, Magnus
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik. Stockholm Univ, Dept Phys, SE-10691 Stockholm, Sweden.;Stockholm Univ, Oskar Klein Ctr Cosmoparticle Phys, SE-10691 Stockholm, Sweden..
    Physical Origin of GeV Emission in the Early Phase of GRB 170405A: Clues from Emission Onsets with Multiwavelength Observations2020Ingår i: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 891, nr 2, artikel-id 106Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The origin of GeV emission from the early epoch of gamma-ray bursts (GRBs) is a widely discussed issue. The long gamma-ray burst GRB 170405A, observed by the Fermi Gamma-ray Space Telescope, showed high-energy emission delayed by similar to 20 s with respect to the X-ray emission, followed by temporally fading gamma-ray emission lasting for similar to 1000 s, as commonly observed in high-energy GRBs. In addition, a high-energy spectral cutoff at similar to 50 MeV was detected in the prompt-emission phase. If this feature is caused by pair-production opacity, the bulk Lorentz factor of the GRB ejecta can be estimated to be Gamma(bulk) = 170-420. Simultaneously with Fermi, GRB 170405A was observed by the Swift/Burst Alert Telescope and X-ray telescope, and a clear optical onset was detected similar to 200 s after the burst by the Swift/Ultraviolet Optical Telescope. By coupling the deceleration time to the derived bulk Lorentz factor, the deceleration time was found to correspond to the delayed onset in the optical band. While the delayed onset in the optical band is evidence that this emission had an external shock origin, the temporally extended emission in the GeV band before the optical onset is hard to reconcile with the standard synchrotron emission from the same external shock. This may imply that the common feature of GeV emission with a power-law decay does not necessarily have the same origin as the optical afterglow in all GRBs detected by the Fermi/Large Area Telescope, particularly in their early epoch. Another mechanism to explain the GeV emission in GRB 170405A may be required, such as an internal shock or inverse Compton emission.

  • 327.
    Armas, Jay
    et al.
    Univ Amsterdam, Inst Theoret Phys, NL-1090 GL Amsterdam, Netherlands.;Dutch Inst Emergent Phenomena, NL-1090 GL Amsterdam, Netherlands..
    Hartong, Jelle
    Univ Edinburgh, Sch Math, Peter Guthrie Tait Rd, Edinburgh EH9 3FD, Midlothian, Scotland.;Univ Edinburgh, Maxwell Inst Math Sci, Peter Guthrie Tait Rd, Edinburgh EH9 3FD, Midlothian, Scotland..
    Have, Emil
    Univ Edinburgh, Sch Math, Peter Guthrie Tait Rd, Edinburgh EH9 3FD, Midlothian, Scotland.;Univ Edinburgh, Maxwell Inst Math Sci, Peter Guthrie Tait Rd, Edinburgh EH9 3FD, Midlothian, Scotland..
    Nielsen, Bjarke F.
    Univ Copenhagen, Niels Bohr Inst, Blegdamsvej 17, DK-2100 Copenhagen O, Denmark..
    Obers, Niels A.
    KTH, Centra, Nordic Institute for Theoretical Physics NORDITA. Univ Copenhagen, Niels Bohr Inst, Blegdamsvej 17, DK-2100 Copenhagen O, Denmark..
    Newton-Cartan submanifolds and fluid membranes2020Ingår i: Physical Review E. Statistical, Nonlinear, and Soft Matter Physics, ISSN 1539-3755, E-ISSN 1550-2376, Vol. 101, nr 6, artikel-id 062803Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We develop the geometric description of submanifolds in Newton-Cartan spacetime. This provides the necessary starting point for a covariant spacetime formulation of Galilean-invariant hydrodynamics on curved surfaces. We argue that this is the natural geometrical framework to study fluid membranes in thermal equilibrium and their dynamics out of equilibrium. A simple model of fluid membranes that only depends on the surface tension is presented and, extracting the resulting stresses, we show that perturbations away from equilibrium yield the standard result for the dispersion of elastic waves. We also find a generalization of the Canham-Helfrich bending energy for lipid vesicles that takes into account the requirements of thermal equilibrium.

  • 328. Atwood, W. B.
    et al.
    Abdo, A. A.
    Ackermann, M.
    Althouse, W.
    Johnson, A. S.
    Klamra, Wlodzimierz
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Pearce, Mark
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Ryde, Felix
    Ziegler, M.
    Carlson, Per
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Conrad, Jan
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Hjalmarsdotter, Linnea
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Moretti, Elena
    University and INFN of Trieste.
    THE LARGE AREA TELESCOPE ON THE FERMI GAMMA-RAY SPACE TELESCOPE MISSION2009Ingår i: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 697, nr 2, s. 1071-1102Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Large Area Telescope (Fermi/LAT, hereafter LAT), the primary instrument on the Fermi Gamma-ray Space Telescope (Fermi) mission, is an imaging, wide field-of-view (FoV), high-energy gamma-ray telescope, covering the energy range from below 20 MeV to more than 300 GeV. The LAT was built by an international collaboration with contributions from space agencies, high-energy particle physics institutes, and universities in France, Italy, Japan, Sweden, and the United States. This paper describes the LAT, its preflight expected performance, and summarizes the key science objectives that will be addressed. On-orbit performance will be presented in detail in a subsequent paper. The LAT is a pair-conversion telescope with a precision tracker and calorimeter, each consisting of a 4 x 4 array of 16 modules, a segmented anticoincidence detector that covers the tracker array, and a programmable trigger and data acquisition system. Each tracker module has a vertical stack of 18 (x, y) tracking planes, including two layers (x and y) of single-sided silicon strip detectors and high-Z converter material (tungsten) per tray. Every calorimeter module has 96 CsI(Tl) crystals, arranged in an eight-layer hodoscopic configuration with a total depth of 8.6 radiation lengths, giving both longitudinal and transverse information about the energy deposition pattern. The calorimeter's depth and segmentation enable the high-energy reach of the LAT and contribute significantly to background rejection. The aspect ratio of the tracker (height/width) is 0.4, allowing a large FoV (2.4 sr) and ensuring that most pair-conversion showers initiated in the tracker will pass into the calorimeter for energy measurement. Data obtained with the LAT are intended to (1) permit rapid notification of high-energy gamma-ray bursts and transients and facilitate monitoring of variable sources, (2) yield an extensive catalog of several thousand high-energy sources obtained from an all-sky survey, (3) measure spectra from 20 MeV to more than 50 GeV for several hundred sources, (4) localize point sources to 0.3-2 arcmin, (5) map and obtain spectra of extended sources such as SNRs, molecular clouds, and nearby galaxies, (6) measure the diffuse isotropic gamma-ray background up to TeV energies, and (7) explore the discovery space for dark matter.

  • 329.
    Aurell, Erik
    et al.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Datavetenskap, Beräkningsvetenskap och beräkningsteknik (CST). Jagiellonian Univ, Fac Phys Astron & Appl Comp Sci, PL-30348 Krakow, Poland..
    Eckstein, Michal
    Jagiellonian Univ, Inst Theoret Phys, Ul Lojasiewicza 11, PL-30348 Krakow, Poland.;Univ Gdansk, Fac Math Phys & Informat, Natl Quantum Informat Ctr, Inst Theoret Phys & Astrophys, Wita Stwosza 57, PL-80308 Gdansk, Poland..
    Horodecki, Pawel
    Univ Gdansk, Int Ctr Theory Quantum Technol, Wita Stwosza 63, PL-80308 Gdansk, Poland.;Gdansk Univ Technol, Fac Appl Phys & Math, Natl Quantum Informat Ctr, Gabriela Narutowicza 11-12, PL-80233 Gdansk, Poland..
    Quantum Black Holes as Solvents2021Ingår i: Foundations of physics, ISSN 0015-9018, E-ISSN 1572-9516, Vol. 51, nr 2, artikel-id 54Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Almost all of the entropy in the universe is in the form of Bekenstein-Hawking (BH) entropy of super-massive black holes. This entropy, if it satisfies Boltzmann's equation S=log N, hence represents almost all the accessible phase space of the Universe, somehow associated to objects which themselves fill out a very small fraction of ordinary three-dimensional space. Although time scales are very long, it is believed that black holes will eventually evaporate by emitting Hawking radiation, which is thermal when counted mode by mode. A pure quantum state collapsing to a black hole will hence eventually re-emerge as a state with strictly positive entropy, which constitutes the famous black hole information paradox. Expanding on a remark by Hawking we posit that BH entropy is a thermodynamic entropy, which must be distinguished from information-theoretic entropy. The paradox can then be explained by information return in Hawking radiation. The novel perspective advanced here is that if BH entropy counts the number of accessible physical states in a quantum black hole, then the paradox can be seen as an instance of the fundamental problem of statistical mechanics. We suggest a specific analogy to the increase of the entropy in a solvation process. We further show that the huge phase volume (N), which must be made available to the universe in a gravitational collapse, cannot originate from the entanglement between ordinary matter and/or radiation inside and outside the black hole. We argue that, instead, the quantum degrees of freedom of the gravitational field must get activated near the singularity, resulting in a final state of the 'entangled entanglement' form involving both matter and gravity.

  • 330.
    Axelsson, Magnus
    Department of Astronomy, Stockholm University.
    Cool Discs, Hot Flows: The Varying Faces of Accreting Compact Objects: Preface2008Ingår i: AIP Conference Proceedings, ISSN 0094-243X, E-ISSN 1551-7616, Vol. 1054, s. vii-Artikel i tidskrift (Övrigt vetenskapligt)
  • 331.
    Axelsson, Magnus
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Photospheric emission from gamma-ray bursts2013Ingår i: EAS Publications Series, 2013, s. 53-57Konferensbidrag (Refereegranskat)
    Abstract [en]

    In spite of extensive research over the past decades, a complete physical picture of the origin of the prompt gamma-ray burst emission is still lacking. During recent years, evidence has been accumulating that the jet photosphere plays an important role. In this paper we summarize the lessons learned from Fermi observations regarding the behavior of the photosphere and discuss why photospheric emission does not necessarily appear as blackbody radiation. We concentrate on two strong and important bursts, GRB 090902B and GRB 110721A, which serve as examples of the standard appearance photospheric emission may have in gamma-ray burst spectra.

  • 332.
    Axelsson, Magnus
    Department of Astronomy, Stockholm University.
    Rapid X-ray variability in Cygnus X-l2008Ingår i: Cool Discs, Hot Flows: The Varying Faces of Accreting Compact Objects, 2008, Vol. 1054, s. 135-141Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, results from temporal analysis of RXTE observations of the black hole binary Cygnus X-l are reviewed. By tapping into the large amount of archival data available, a systematic study of the variability, in the form of the power spectrum, is conducted. It is clear that timing studies can give valuable information on the emission mechanisms and accretion geometry. Tying characteristic frequencies to effects predicted by general relativity directly gives information about the parameters of the compact object. The results show that the characteristic frequencies seen in the power spectrum follow the relation predicted for the nodal and periastron precessional frequencies of relativistic precession. From this relation, the spin of the black hole is determined to a*=0.48±0.01 for a mass of 9 M⊙. During times of high hardness, the hardness-flux correlation seen in the hard state of the source disappears on short timescales. Together with the variable characteristic frequencies, this is interpreted as support for the truncated disk scenario.

  • 333.
    Axelsson, Magnus
    et al.
    Department of Astronomy, Stockholm University.
    Borgonovo, Luis
    Department of Astronomy, Stockholm University.
    Larsson, S.
    Probing the temporal variability of Cygnus X-1 into the soft state2006Ingår i: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 452, nr 3, s. 975-984Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Building on results from previous studies of Cygnus X-1, we analyze Rossi X-ray Timing Explorer (RXTE) data taken when the source was in the soft and transitional spectral states. We look at the power spectrum in the 0.01-50 Hz range, using a model consisting of a cut-off power-law and two Lorentzian components. We are able to constrain the relation between the characteristic frequencies of the Lorentzian components, and show that it is consistent with a power-law relation having the same index (1.2) as previously reported for the hard state, but shifted by a factor ∌2. Furthermore, it is shown that the change in the frequency relation seen during the transitions can be explained by invoking a shift of one Lorentzian component to a higher harmonic, and we explore the possible support for this interpretation in the other component parameters. With the improved soft state results we study the evolution of the fractional variance for each temporal component. This approach indicates that the two Lorentzian components are connected to each other, and unrelated to the power-law component in the power spectrum, pointing to at least two separate emission components.

  • 334.
    Axelsson, Magnus
    et al.
    Department of Astronomy, Stockholm University.
    Borgonovo, Luis
    Department of Astronomy, Stockholm University.
    Larsson, Stefan
    Evolution of the 0.01-25 Hz power spectral components in Cygnus X-12005Ingår i: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 438, nr 3, s. 999-1012Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Analyzing the archival data from the Rossi X-ray Timing Explorer (RXTE), we study the power density spectra (PDS) of Cygnus X-1 from 1996 to 2003 in the frequency range of 0.01-25 Hz. Using a model consisting of one or two Lorentzians and/or an exponentially cut-off power-law, we are able to achieve a good fit to the PDS during the observations. With our model we are also able to track the evolution of the Lorentzian components through all spectral states of the source. We confirm the relation between characteristic frequencies seen both in black hole candidate and neutron star sources, and show the changes in this relation during the transitional and soft states of the source. The connection between the Lorentzian components is investigated by analyzing similarities and differences in their behavior. We find that the spectral state of the source can be uniquely determined from the parameters of these components. The parameter correlations can all be described by continuous functions, which differ between components. We discuss our results in the context of relativistic precession model for the accretion disk, and show a remarkable agreement between the model prediction and the data in the hard state. We estimate a value for the specific angular momentum of a* = 0.49 (-0.57) in the case of prograde (retrograde) rotation and an estimate for the inner radius of 22 to 50 (25 to 55) gravitational radii. Additional assumptions are required to explain the soft state data, and attempting to invoke rotational reversal for state transitions shows that it is insufficient to explain the differences between the hard and soft state data. © ESO 2005.

  • 335.
    Axelsson, Magnus
    et al.
    Lund Observatory, Lund University.
    Church, Ross P.
    Davies, Melvyn B.
    Levan, Andrew J.
    Ryde, Felix
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    On the origin of black hole spin in high-mass black hole binaries: Cygnus X-12011Ingår i: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 412, nr 4, s. 2260-2264Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    To date, there have been several detections of high-mass black hole binaries in both the Milky Way and other galaxies. For some of these, the spin parameter of the black hole has been estimated. As many of these systems are quite tight, a suggested origin of the spin is angular momentum imparted by the synchronous rotation of the black hole progenitor with its binary companion. Using Cygnus X-1, the best studied high-mass black hole binary, we investigate this possibility. We find that such an origin of the spin is not likely, and our results point rather to the spin being the result of processes during the collapse.

  • 336.
    Axelsson, Magnus
    et al.
    Department of Astronomy, Stockholm University.
    Hjalmarsdotter, L.
    Borgonovo, L.
    Larsson, S.
    Vanishing hardness-flux correlation in Cygnus X-1: Signs of the disc moving out2008Ingår i: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 490, nr 1, s. 253-258Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Aims. We investigate observations of the X-ray binary Cygnus X-1 with unusually high hardness and low flux. In particular, we study the characteristic frequencies seen in the PDS and the hardness-flux correlation within and between these observations.Methods. We analyse observations of Cyg X-1 during periods when the source reaches its highest hardness levels (≳ 1 for the 9-20 keV over 2-4 keV RXTE/PCA count ratios, corresponding to Γ ≲ 1.6). Using the relativistic precession model to interpret the PDS, we estimate a value for the inner radius of the accretion disc. We also study the hardness-flux correlation.Results. In the selected observations, the characteristic frequencies seen in the power spectrum are shifted to the lowest end of their frequency range. Within a single observation, the hardness-flux correlation is very weak, contrary to the negative correlation normally observed in the hard state. We suggest that this could be interpreted as the inner disc boundary being at large radii (≳50Rg), thereby requiring more time to adjust to a changing accretion rate than allowed by a single RXTE observation, and compare our findings to estimates of the viscous time scale responsible for small scale variability in the system.

  • 337.
    Axelsson, Magnus
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Jackson, Miranda
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Lundman, Christoffer
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Moretti, Elena
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Nymark, Tanja
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Pe'Er, A.
    et al.,
    GRB110721A: An extreme peak energy and signatures of the photosphere2012Ingår i: The Astrophysical Journal. Letters, ISSN 2041-8205, Vol. 757, nr 2, s. L31-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    GRB110721A was observed by the Fermi Gamma-ray Space Telescope using its two instruments the Large Area Telescope (LAT) and the Gamma-ray Burst Monitor (GBM). The burst consisted of one major emission episode which lasted for ~24.5 seconds (in the GBM) and had a peak flux of 5.7\pm0.2 x 10^{-5} erg/s/cm^2. The time-resolved emission spectrum is best modeled with a combination of a Band function and a blackbody spectrum. The peak energy of the Band component was initially 15\pm2 MeV, which is the highest value ever detected in a GRB. This measurement was made possible by combining GBM/BGO data with LAT Low Energy Events to achieve continuous 10--100 MeV coverage. The peak energy later decreased as a power law in time with an index of -1.89\pm0.10. The temperature of the blackbody component also decreased, starting from ~80 keV, and the decay showed a significant break after ~2 seconds. The spectrum provides strong constraints on the standard synchrotron model, indicating that alternative mechanisms may give rise to the emission at these energies.

  • 338.
    Axelsson, Magnus
    et al.
    Department of Astronomy, Stockholm University.
    Larsson, S.
    Hjalmarsdotter, L.
    The aperiodic broad-band X-ray variability of Cygnus X-32009Ingår i: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 394, nr 3, s. 1544-1550Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We study the soft X-ray variability of Cygnus X-3. By combining data from the All-Sky Monitor and Proportional Counter Array instruments on the RXTE satellite with EXOSAT/Medium Energy (ME) detector observations, we are able to analyse the power density spectrum (PDS) of the source from 10-9 to 0.1 Hz, thus covering time-scales from seconds to years. As the data on the longer time-scales are unevenly sampled, we combine traditional power spectral techniques with simulations to analyse the variability in this range. The PDS at higher frequencies (≳10-3 Hz) are for the first time compared for all states of this source. We find that it is for all states well described by a power law, with index ∌ -2 in the soft states and a tendency for a less steep power law in the hard state. At longer time-scales, we study the effect of the state transitions on the PDS, and find that the variability below ∌10-7 Hz is dominated by the transitions. Furthermore, we find no correlation between the length of a high/soft-state episode and the time since the previous high/soft state. On intermediate time-scales, we find evidence for a break in the PDS at time-scales of the order of the orbital period. This may be interpreted as evidence for the existence of a tidal resonance in the accretion disc around the compact object, and constraining the mass ratio to M2/M1 ≲ 0.3.

  • 339.
    Axelsson, Magnus
    et al.
    Department of Astronomy, Stockholm University.
    Ryde, FelixDepartment of Astronomy, Stockholm University.
    Gamma-Ray Bursts: Prospects for Glast2007Proceedings (redaktörskap) (Övrigt vetenskapligt)
  • 340.
    Axelsson, Magnus
    et al.
    Department of Astronomy, Stockholm University.
    Ryde, Felix
    Department of Astronomy, Stockholm University.
    Gamma-Ray Bursts: Prospects for GLAST: Preface2007Ingår i: AIP Conference Proceedings, Stockholm, 2007, Vol. 906, s. vii-Konferensbidrag (Övrigt vetenskapligt)
  • 341.
    Axelsson, Magnus
    et al.
    Stockholm Univ, Oskar Klein Ctr CosmoParticle Phys, Dept Phys, SE-10691 Stockholm, Sweden.;Stockholm Univ, Dept Astron, SE-10691 Stockholm, Sweden..
    Veledina, Alexandra
    KTH, Centra, Nordic Institute for Theoretical Physics NORDITA. Univ Turku, Dept Phys & Astron, FI-20014 Turku, Finland.;;Stockholm Univ, Roslagstullshacken 23, SE-10691 Stockholm, Sweden.;Russian Acad Sci, Space Res Inst, Profsoyuznaya Str 84-32, Moscow 117997, Russia..
    Accretion geometry of the black hole binary MAXI J1820+070 probed by frequency-resolved spectroscopy2021Ingår i: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 507, nr 2, s. 2744-2754Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The geometry of the inner accretion flow in the hard and hard-intermediate states of X-ray binaries remains controversial. Using Neutron star Interior Composition Explorer observations of the black hole X-ray binary MAXI J1820+070 during the rising phase of its 2018 outburst, we study the evolution of the timing properties, in particular the characteristic variability frequencies of the prominent iron K alpha line. Using frequency-resolved spectroscopy, which is robust against uncertainties in the line profile modelling, we find that reflection occurs at large distances from the Comptonizing region in the bright hard state. During the hard-to-soft transition, the variability properties suggest that the reflector moves closer to the X-ray source. In parallel, the peak of the iron line shifts from 6.5 to similar to 7keV, becoming consistent with that expected of from a highly inclined disc extending close to the black hole. We additionally find significant changes in the dependence of the root-mean-square (rms) variability on both energy and Fourier frequency as the source softens. The evolution of the rms-energy dependence, the line profile, and the timing properties of the iron line as traced by the frequency-resolved spectroscopy all support the picture of a truncated disc/inner flow geometry.

  • 342.
    Bagheri, Mahdi
    et al.
    School of Physics, Center for Relativistic Astrophysics, Georgia Institute of Technology, 837 State Street NW, Atlanta, 30332-0430, GA, United States.
    Capel, Francesca
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Carlson, Per
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Eliasson, Linda
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Fuglesang, Christer
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Yashin, I. V.
    Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, Russian Federation.
    et al.,
    Overview of Cherenkov Telescope on-board EUSO-SPB2 for the Detection of Very-High-Energy Neutrinos2022Ingår i: Proceedings of Science, Sissa Medialab Srl , 2022, Vol. 395, artikel-id 1191Konferensbidrag (Refereegranskat)
    Abstract [en]

    We present the status of the development of a Cherenkov telescope to be flown on a long-duration balloon flight, the Extreme Universe Space Observatory Super Pressure Balloon 2 (EUSO-SPB2). EUSO-SPB2 is an approved NASA balloon mission that is planned to fly in 2023 and is a precursor of the Probe of Extreme Multi-Messenger Astrophysics (POEMMA), a candidate for an Astrophysics probe-class mission. The purpose of the Cherenkov telescope on-board EUSOSPB2 is to classify known and unknown sources of backgrounds for future space-based neutrino detectors. Furthermore, we will use the Earth-skimming technique to search for Very-High-Energy (VHE) tau neutrinos below the limb (E > 10 PeV) and observe air showers from cosmic rays above the limb. The 0.785 m2 Cherenkov telescope is equipped with a 512-pixel SiPM camera covering a 12.8° x 6.4° (Horizontal × Vertical) field of view. The camera signals are digitized with a 100 MS/s readout system. In this paper, we discuss the status of the telescope development, the camera integration, and simulation studies of the camera response.

  • 343.
    Balatsky, Alexander V.
    et al.
    KTH, Centra, Nordic Institute for Theoretical Physics NORDITA. Stockholm Univ, Roslagstullbacken 23, SE-10691 Stockholm, Sweden.;Univ Connecticut, Dept Phys, Storrs, CT 06269 USA.;Univ Connecticut, Inst Mat Sci, Storrs, CT 06269 USA..
    Fraser, Benjo
    Stockholm Univ, Roslagstullbacken 23, SE-10691 Stockholm, Sweden..
    Roising, Henrik S.
    Stockholm Univ, Roslagstullbacken 23, SE-10691 Stockholm, Sweden..
    Dark sound: Collective modes of the axionic dark matter condensate2022Ingår i: Physical Review D: covering particles, fields, gravitation, and cosmology, ISSN 2470-0010, E-ISSN 2470-0029, Vol. 105, nr 2, artikel-id 023504Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We discuss the axion dark matter (DM) condensate and the consequences the interactions of dark matter would have on the spectrum of collective modes. We find that DM self-interactions change the spectrum of excitations from a quadratic to a linearlike dispersion with velocity upsilon(s) which is set by the interactions, but dominated by gravity. For typical DM densities and interactions we find upsilon(s) similar to 10(-12)c. This soundlike mode corresponds to DM density oscillations just like in any other Bose liquid, hence we call it dark sound (DS). The DS mode is well defined and describes stable density oscillations at intermediate length scales k >= k(min) similar to 10(4) lyr(-1). In the extreme long-wavelength limit gravity dominates and leads to Jeans instability of the sound mode at the scale of clump formation k <= k(mi)(n). We also discuss the possible observable consequences of the DS, including quantized DS modes inside clumps, their characteristic energy, and noise features that might facilitate the observation of DM.

  • 344. Balazs, Csaba
    et al.
    Li, Tong
    Savage, Chris
    KTH, Centra, Nordic Institute for Theoretical Physics NORDITA. University of Utah, United States.
    White, Martin
    Interpreting the Fermi-LAT gamma ray excess in the simplified framework2015Ingår i: Physical Review D, ISSN 1550-7998, E-ISSN 1550-2368, Vol. 92, nr 12, artikel-id 123520Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We test the plausibility of the hypothesis that the annihilation of a Majorana fermion dark matter particle via a scalar mediator explains the gamma ray excess from the Galactic center. Assuming that the mediator couples to all third generation fermions we calculate observables for dark matter abundance and scattering on nuclei, gamma, positron, and antiproton cosmic ray fluxes, radio emission from dark matter annihilation, and the effect of dark matter annihilations on the CMB. After discarding the controversial radio observation, we show that the dark matter model simultaneously fits the observed excesses in the cosmic gamma ray, the positron, and antiproton fluxes, while evading constraints from the CMB and direct detection. The experimental data are consistent with a dark matter (mediator) mass in the 10-100 (3-1000) GeV region and with weakly correlated couplings to bottom quarks and tau leptons with values of 10(-3) - 1 at the 68% credibility level.

  • 345.
    Baldini, L.
    et al.
    Univ Pisa, I-56127 Pisa, Italy.;Ist Nazl Fis Nucl, Sez Pisa, I-56127 Pisa, Italy..
    Cavazzuti, E.
    Via Politecn Snc, Italian Space Agcy, I-00133 Rome, Italy..
    Johannesson, G.
    Univ Iceland, Sci Inst, IS-107 Reykjavik, Iceland.;Royal Inst Technol, NORDITA, Roslagstullsbacken 23, SE-10691 Stockholm, Sweden.;Stockholm Univ, Roslagstullsbacken 23, SE-10691 Stockholm, Sweden..
    Larsson, Stefan
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik. Dalarna Univ, Sch Educ Hlth & Social Studies, Nat Sci, SE-79188 Falun, Sweden..
    Zaharijas, G.
    Ist Nazl Fis Nucl, Sez Trieste, I-34127 Trieste, Italy.;Univ Trieste, I-34127 Trieste, Italy.;Univ Nova Gorica, Ctr Astrophys & Cosmol, Nova Gorica, Slovenia..
    Catalog of Long-term Transient Sources in the First 10 yr of Fermi-LAT Data2021Ingår i: Astrophysical Journal Supplement Series, ISSN 0067-0049, E-ISSN 1538-4365, Vol. 256, nr 1, artikel-id 13Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We present the first Fermi Large Area Telescope (LAT) catalog of long-term gamma-ray transient sources (1FLT). This comprises sources that were detected on monthly time intervals during the first decade of Fermi-LAT operations. The monthly timescale allows us to identify transient and variable sources that were not yet reported in other Fermi-LAT catalogs. The monthly data sets were analyzed using a wavelet-based source detection algorithm that provided the candidate new transient sources. The search was limited to the extragalactic regions of the sky to avoid the dominance of the Galactic diffuse emission at low Galactic latitudes. The transient candidates were then analyzed using the standard Fermi-LAT maximum likelihood analysis method. All sources detected with a statistical significance above 4 sigma in at least one monthly bin were listed in the final catalog. The 1FLT catalog contains 142 transient gamma-ray sources that are not included in the 4FGL-DR2 catalog. Many of these sources (102) have been confidently associated with active galactic nuclei (AGNs): 24 are associated with flat-spectrum radio quasars, 1 with a BL Lac object, 70 with blazars of uncertain type, 3 with radio galaxies, 1 with a compact steep-spectrum radio source, 1 with a steep-spectrum radio quasar, and 2 with AGNs of other types. The remaining 40 sources have no candidate counterparts at other wavelengths. The median gamma-ray spectral index of the 1FLT-AGN sources is softer than that reported in the latest Fermi-LAT AGN general catalog. This result is consistent with the hypothesis that detection of the softest gamma-ray emitters is less efficient when the data are integrated over year-long intervals.

  • 346.
    Bale, S. D.
    et al.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA.;Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA..
    Goetz, K.
    Univ Minnesota, Sch Phys & Astron, Minneapolis, MN 55455 USA..
    Harvey, P. R.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA..
    Turin, P.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA..
    Bonnell, J. W.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA..
    Dudok de Wit, T.
    CNRS, LPC2E, 3A Ave Rech Sci, Orleans, France..
    Ergun, R. E.
    Univ Colorado, Lab Atmospher & Space Phys, Boulder, CO USA..
    MacDowall, R. J.
    NASA, Goddard Space Flight Ctr, Greenbelt, MD USA..
    Pulupa, M.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA..
    André, Mats
    Uppsala universitet, Institutet för rymdfysik, Uppsalaavdelningen.
    Bolton, M.
    Univ Colorado, Lab Atmospher & Space Phys, Boulder, CO USA..
    Bougeret, J. -L
    Bowen, T. A.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA.;Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA..
    Burgess, D.
    Queen Mary Univ London, Astron Unit, London, England..
    Cattell, C. A.
    Univ Minnesota, Sch Phys & Astron, Minneapolis, MN 55455 USA..
    Chandran, B. D. G.
    Univ New Hampshire, Dept Phys, Durham, NH 03824 USA..
    Chaston, C. C.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA..
    Chen, C. H. K.
    Imperial Coll, Dept Phys, London, England..
    Choi, M. K.
    NASA, Goddard Space Flight Ctr, Greenbelt, MD USA..
    Connerney, J. E.
    NASA, Goddard Space Flight Ctr, Greenbelt, MD USA..
    Cranmer, S.
    Univ Colorado, Lab Atmospher & Space Phys, Boulder, CO USA..
    Diaz-Aguado, M.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA..
    Donakowski, W.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA..
    Drake, J. F.
    Univ Maryland, Dept Phys, College Pk, MD 20742 USA..
    Farrell, W. M.
    NASA, Goddard Space Flight Ctr, Greenbelt, MD USA..
    Fergeau, P.
    CNRS, LPC2E, 3A Ave Rech Sci, Orleans, France..
    Fermin, J.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA..
    Fischer, J.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA..
    Fox, N.
    Johns Hopkins Univ, Appl Phys Lab, Laurel, MD USA..
    Glaser, D.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA..
    Goldstein, M.
    NASA, Goddard Space Flight Ctr, Greenbelt, MD USA..
    Gordon, D.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA..
    Hanson, E.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA.;Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA..
    Harris, S. E.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA..
    Hayes, L. M.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA..
    Hinze, J. J.
    Univ Minnesota, Sch Phys & Astron, Minneapolis, MN 55455 USA..
    Hollweg, J. V.
    Univ New Hampshire, Dept Phys, Durham, NH 03824 USA..
    Horbury, T. S.
    Imperial Coll, Dept Phys, London, England..
    Howard, R. A.
    Naval Res Lab, Washington, DC 20375 USA..
    Hoxie, V.
    Univ Colorado, Lab Atmospher & Space Phys, Boulder, CO USA..
    Jannet, G.
    CNRS, LPC2E, 3A Ave Rech Sci, Orleans, France..
    Karlsson, M.
    Univ Colorado, Lab Atmospher & Space Phys, Boulder, CO USA..
    Kasper, J. C.
    Univ Michigan, Ann Arbor, MI 48109 USA..
    Kellogg, P. J.
    Univ Minnesota, Sch Phys & Astron, Minneapolis, MN 55455 USA..
    Kien, M.
    Univ Colorado, Lab Atmospher & Space Phys, Boulder, CO USA..
    Klimchuk, J. A.
    NASA, Goddard Space Flight Ctr, Greenbelt, MD USA..
    Krasnoselskikh, V. V.
    CNRS, LPC2E, 3A Ave Rech Sci, Orleans, France..
    Krucker, S.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA..
    Lynch, J. J.
    Univ Minnesota, Sch Phys & Astron, Minneapolis, MN 55455 USA..
    Maksimovic, M.
    Observ Paris, LESIA, Meudon, France..
    Malaspina, D. M.
    Univ Colorado, Lab Atmospher & Space Phys, Boulder, CO USA..
    Marker, S.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA..
    Martin, P.
    CNRS, LPC2E, 3A Ave Rech Sci, Orleans, France..
    Martinez-Oliveros, J.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA..
    McCauley, J.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA..
    McComas, D. J.
    Southwest Res Inst, San Antonio, TX USA..
    McDonald, T.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA..
    Meyer-Vernet, N.
    Observ Paris, LESIA, Meudon, France..
    Moncuquet, M.
    Observ Paris, LESIA, Meudon, France..
    Monson, S. J.
    Univ Minnesota, Sch Phys & Astron, Minneapolis, MN 55455 USA..
    Mozer, F. S.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA..
    Murphy, S. D.
    NASA, Goddard Space Flight Ctr, Greenbelt, MD USA..
    Odom, J.
    NASA, Goddard Space Flight Ctr, Greenbelt, MD USA..
    Oliverson, R.
    NASA, Goddard Space Flight Ctr, Greenbelt, MD USA..
    Olson, J.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA..
    Parker, E. N.
    Univ Chicago, Dept Astron & Astrophys, 5640 S Ellis Ave, Chicago, IL 60637 USA..
    Pankow, D.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA..
    Phan, T.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA..
    Quataert, E.
    Univ Calif Berkeley, Dept Astron, 601 Campbell Hall, Berkeley, CA 94720 USA..
    Quinn, T.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA..
    Ruplin, S. W.
    Praxis Studios, Brooklyn, NY USA..
    Salem, C.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA..
    Seitz, D.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA..
    Sheppard, D. A.
    NASA, Goddard Space Flight Ctr, Greenbelt, MD USA..
    Siy, A.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA..
    Stevens, K.
    Univ Colorado, Lab Atmospher & Space Phys, Boulder, CO USA..
    Summers, D.
    Univ Colorado, Lab Atmospher & Space Phys, Boulder, CO USA..
    Szabo, A.
    NASA, Goddard Space Flight Ctr, Greenbelt, MD USA..
    Timofeeva, M.
    CNRS, LPC2E, 3A Ave Rech Sci, Orleans, France..
    Vaivads, Andris
    Uppsala universitet, Institutet för rymdfysik, Uppsalaavdelningen.
    Velli, M.
    UCLA, Earth Planetary & Space Sci, Los Angeles, CA USA..
    Yehle, A.
    Univ Colorado, Lab Atmospher & Space Phys, Boulder, CO USA..
    Werthimer, D.
    Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA..
    Wygant, J. R.
    Univ Minnesota, Sch Phys & Astron, Minneapolis, MN 55455 USA..
    The FIELDS Instrument Suite for Solar Probe Plus2016Ingår i: Space Science Reviews, ISSN 0038-6308, E-ISSN 1572-9672, Vol. 204, nr 1-4, s. 49-82Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    NASA's Solar Probe Plus (SPP) mission will make the first in situ measurements of the solar corona and the birthplace of the solar wind. The FIELDS instrument suite on SPP will make direct measurements of electric and magnetic fields, the properties of in situ plasma waves, electron density and temperature profiles, and interplanetary radio emissions, amongst other things. Here, we describe the scientific objectives targeted by the SPP/FIELDS instrument, the instrument design itself, and the instrument concept of operations and planned data products.

    Ladda ner fulltext (pdf)
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  • 347. Band, D. L.
    et al.
    Axelsson, Magnus
    Ist Nazl Fis Nucl, Sez Pisa, Pisa, Italy .
    Battelino, Milan
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    McGlynn, Sinéad
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Moretti, Elena
    University and INFN of Trieste.
    Ryde, Felix
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Yamazaki, R.
    et al.,
    PROSPECTS FOR GRB SCIENCE WITH THE FERMI LARGE AREA TELESCOPE2009Ingår i: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 701, nr 2, s. 1673-1694Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    The Large Area Telescope (LAT) instrument on the Fermi mission will reveal the rich spectral and temporal gamma-ray burst (GRB) phenomena in the > 100 MeV band. The synergy with Fermi's Gamma-ray Burst Monitor detectors will link these observations to those in the well explored 10-1000 keV range; the addition of the > 100 MeV band observations will resolve theoretical uncertainties about burst emission in both the prompt and afterglow phases. Trigger algorithms will be applied to the LAT data both onboard the spacecraft and on the ground. The sensitivity of these triggers will differ because of the available computing resources onboard and on the ground. Here we present the LAT's burst detection methodologies and the instrument's GRB capabilities.

  • 348. Banerjee, D. P. K.
    et al.
    Varricatt, W. P.
    Mathew, Blesson
    Launila, Olli
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik.
    Ashok, N. M.
    THE A-X INFRARED BANDS OF ALUMINUM OXIDE IN STARS: SEARCH AND NEW DETECTIONS2012Ingår i: Astrophysical journal Letters, ISSN 2041-8205, Vol. 753, nr 1, s. L20-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We describe a search for the A-X infrared bands of AlO with a view toward better understanding the characteristics of this radical. These bands are infrequently encountered in astronomical sources but surprisingly were very prominent in the spectra of two well-known, novalike variables (V838 Mon and V4332 Sgr) thereby motivating us to explore the physical conditions necessary for their excitation. In this study, we present the detection of A-X bands in the spectra of 13 out of 17 stars, selected on the basis of their J-K colors as potential candidates for detection of these bands. The majority of the AlO detections are in asymptotic giant branch (AGB) stars, viz., nine OH/IR stars, two Mira variables, and two bright infrared sources. Our study shows that the A-X bands are fairly prevalent in sources with low temperature and O-rich environments. Interesting variation in the strength of the AlO bands in one of the sources (IRAS 18530+0817) is reported and the cause for this is examined. Possible applications of the present study are discussed in terms of the role of AlO in alumina dust formation, the scope for estimating the radioactive Al-26 content in AGB stars from the A-X bands, and providing possible targets for further mm/radio studies of AlO which has recently been discovered at millimeter wavelengths.

  • 349. Barbiellini, G.
    et al.
    Bastieri, D.
    Bechtol, K.
    Bellazzini, R.
    Blandford, R. D.
    Borgland, A. W.
    Bregeon, J.
    Bruel, P.
    Buehler, R.
    Buson, S.
    Caliandro, G. A.
    Cameron, R. A.
    Caraveo, P. A.
    Cavazzuti, E.
    Cecchi, C.
    Chaves, R. C. G.
    Chekhtman, A.
    Cheung, C. C.
    Chiang, J.
    Ciprini, S.
    Claus, R.
    Cohen-Tanugi, J.
    D'Ammando, F.
    de Angelis, A.
    Dermer, C. D.
    Digel, S. W.
    do Couto e Silva, E.
    Drell, P. S.
    Drlica-Wagner, A.
    Favuzzi, C.
    Focke, W. B.
    Franckowiak, A.
    Fukazawa, Y.
    Fusco, P.
    Gargano, F.
    Gasparrini, D.
    Germani, S.
    Giglietto, N.
    Giommi, P.
    Giordano, F.
    Giroletti, M.
    Glanzman, T.
    Godfrey, G.
    Grenier, I. A.
    Grove, J. E.
    Guiriec, S.
    Hadasch, D.
    Hayashida, M.
    Hays, E.
    Hughes, R. E.
    Jackson, Miranda S.
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Jogler, T.
    Knoedlseder, J.
    Kuss, M.
    Lande, J.
    Larsson, S.
    Longo, F.
    Loparco, F.
    Lovellette, M. N.
    Lubrano, P.
    Mazziotta, M. N.
    Mehault, J.
    Michelson, P. F.
    Mizuno, T.
    Moiseev, A. A.
    Monte, C.
    Monzani, M. E.
    Morselli, A.
    Moskalenko, I. V.
    Murgia, S.
    Nemmen, R.
    Nuss, E.
    Ohsugi, T.
    Omodei, N.
    Orienti, M.
    Orlando, E.
    Paneque, D.
    Perkins, J. S.
    Piron, F.
    Pivato, G.
    Prokhorov, D.
    Raino, S.
    Razzano, M.
    Razzaque, S.
    Reimer, A.
    Reimer, O.
    Ritz, S.
    Romoli, C.
    Sanchez-Conde, M.
    Sanchez, D. A.
    Sgro, C.
    Siskind, E. J.
    Spandre, G.
    Spinelli, P.
    Takahashi, H.
    Tanaka, T.
    Tibaldo, L.
    Tinivella, M.
    Tosti, G.
    Troja, E.
    Usher, T. L.
    Vandenbroucke, J.
    Vasileiou, V.
    Vianello, G.
    Vitale, V.
    Waite, A. P.
    Winer, B. L.
    Wood, K. S.
    Yang, Z.
    Fermi large area telescope observations of blazar 3C 279 occultations by the sun2014Ingår i: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 784, nr 2, s. 118-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Observations of occultations of bright. gamma-ray sources by the Sun may reveal predicted pair halos around blazars and/or new physics, such as, e.g., hypothetical light dark matter particles-axions. We use Fermi Gamma-Ray Space Telescope (Fermi) data to analyze four occultations of blazar 3C 279 by the Sun on October 8 each year from 2008 to 2011. A combined analysis of the observations of these occultations allows a point-like source at the position of 3C 279 to be detected with significance of approximate to 3 sigma, but does not reveal any significant excess over the flux expected from the quiescent Sun. The likelihood ratio test rules out complete transparency of the Sun to the blazar. gamma-ray emission at a 3s confidence level.

  • 350.
    Barclay, Krister D. G.
    et al.
    Embry Riddle Aeronaut Univ, Phys & Astron, 3700 Willow Creek Rd, Prescott, AZ 86301 USA.;SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA..
    Rosu, Sophie
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Richardson, Noel D.
    Embry Riddle Aeronaut Univ, Phys & Astron, 3700 Willow Creek Rd, Prescott, AZ 86301 USA..
    Chene, Andre-Nicolas
    US ELTP NSFs NOIRLab, 670 N Aohoku Pl, Hilo, HI 96720 USA..
    St-Louis, Nicole
    Univ Montreal, Dept Phys, Complexe Sci, 1375 Ave Therese Lavoie Roux, Montreal, PQ H2V 0B3, Canada..
    Ignace, Richard
    East Tennessee State Univ, Dept Phys & Astron, Johnson City, TN 37614 USA..
    Moffat, Anthony F. J.
    Univ Montreal, Dept Phys, Complexe Sci, 1375 Ave Therese Lavoie Roux, Montreal, PQ H2V 0B3, Canada..
    Using CHIRON spectroscopy to test the hypothesis of a precessing orbit for the WN4 star EZ CMa2023Ingår i: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 527, nr 2, s. 2198-2208Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The bright WN4 star EZ CMa exhibits a 3.77 d periodicity in photometry , spectroscopy , and polarimetry , but the variations in the measurements are not strictly phase-locked, exhibiting changes in reference times, amplitudes, and the shape of the variability happening over times as short as a few weeks. Recently, 137 d of contiguous, variable photometry from BRITE-constellation was interpreted as caused either by large-scale dense wind structures modulated by rotation, or by a fast-precessing binary having a slightly shorter 3.626 d orbital period and a fast apsidal motion rate of 1315(degrees) yr( -1). We aim at testing the latter hypothesis through analysis of spectroscopy and focus on the N V lambda 4945 line. We derive an orbital solution for the system and reject the 3.626 d period to represent the variations in the radial velocities of EZ CMa. An orbital solution with an orbital period of 3.77 d was obtained but at the cost of an extremely high and thus improbable apsidal motion rate. Our best orbital solution yields a period of 3.751 +/- 0.001 d with no apsidal motion. We place our results in the context of other variability studies and system properties. While we cannot fully reject the precessing binary model, we find that the corotating interaction region (CIR) hypothesis is better supported by these and other data through qualitative models of CIRs.

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