Endre søk
Begrens søket
293031323334 1551 - 1600 of 1688
RefereraExporteraLink til resultatlisten
Permanent link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Treff pr side
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sortering
  • Standard (Relevans)
  • Forfatter A-Ø
  • Forfatter Ø-A
  • Tittel A-Ø
  • Tittel Ø-A
  • Type publikasjon A-Ø
  • Type publikasjon Ø-A
  • Eldste først
  • Nyeste først
  • Skapad (Eldste først)
  • Skapad (Nyeste først)
  • Senast uppdaterad (Eldste først)
  • Senast uppdaterad (Nyeste først)
  • Disputationsdatum (tidligste først)
  • Disputationsdatum (siste først)
  • Standard (Relevans)
  • Forfatter A-Ø
  • Forfatter Ø-A
  • Tittel A-Ø
  • Tittel Ø-A
  • Type publikasjon A-Ø
  • Type publikasjon Ø-A
  • Eldste først
  • Nyeste først
  • Skapad (Eldste først)
  • Skapad (Nyeste først)
  • Senast uppdaterad (Eldste først)
  • Senast uppdaterad (Nyeste først)
  • Disputationsdatum (tidligste først)
  • Disputationsdatum (siste først)
Merk
Maxantalet träffar du kan exportera från sökgränssnittet är 250. Vid större uttag använd dig av utsökningar.
  • 1551. Pe’Er, A.
    et al.
    Ryde, Felix
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Theoretical Implications of Thermal Emission from Gamma-Ray Bursts2009Inngår i: GAMMA-RAY BURST / [ed] Meegan, C; Gehrels, N; Kouveliotou, C, 2009, Vol. 1133, s. 317-322Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Recent analysis show evidence for a thermal emission component that accompanies the non-thermal emission during the prompt phase of GRBs. We show that this component is naturally explained by considering emission from the photosphere. The photosphere of a relativistically expanding plasma wind strongly depends on the angle to the line of sight, θs. As a result, thermal emission can be seen after tens of seconds. Using probability density function P(r,θs) to describe photon escape at radius r and angle θs, we show that the thermal flux is expected to decay at late times as F$_BB$~t$^-2$, and the observed temperature decays as T~t$^-α$, with α~1/2-2/3. We discuss the relation between thermal emission and high energy, non-thermal spectra observed by FERMI. We show how thermal emission can be used to directly measure the Lorentz factor of the flow and the initial radius of the jet.

  • 1552. Pe’Er, A.
    et al.
    Zhang, B. -B
    Ryde, Felix
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    McGlynn, Sinead
    KTH, Skolan för teknikvetenskap (SCI), Fysik.
    Zhang, B.
    Preece, R. D.
    Kouveliotou, C.
    The connection between thermal and non-thermal emission in gamma-ray bursts: general considerations and GRB090902B as a case study2012Inngår i: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 420, nr 1, s. 468-482Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Photospheric (thermal) emission is inherent to the gamma-ray burst (GRB) 'fireball' model. We show here that inclusion of this component in the analysis of the GRB prompt emission phase naturally explains some of the prompt GRB spectra seen by the Fermi satellite over its entire energy band. The sub-MeV peak is explained as multicolour blackbody emission, and the high-energy tail, extending up to the GeV band, results from roughly similar contributions of synchrotron emission, synchrotron self-Compton and Comptonization of the thermal photons by energetic electrons originating after dissipation of the kinetic energy above the photosphere. We show how this analysis method results in a complete, self-consistent picture of the physical conditions at both emission sites of the thermal and non-thermal radiation. We study the connection between the thermal and non-thermal parts of the spectrum, and show how the values of the free model parameters are deduced from the data. We demonstrate our analysis method on GRB090902B: we deduce a Lorentz factor in the range 920 <= eta <= 1070, photospheric radius r(ph) similar or equal to 7.2-8.4 x 10(11) cm and dissipation radius r(gamma) >= 3.5-4.1 x 10(15) cm. By comparison to afterglow data, we deduce that a large fraction epsilon(d) approximate to 85-95 per cent of the kinetic energy is dissipated, and that a large fraction, similar to equipartition of this energy, is carried by the electrons and the magnetic field. This high value of epsilon(d) questions the 'internal shock' scenario as the main energy dissipation mechanism for this GRB.

  • 1553. Pe’Er, A.
    et al.
    Zhang, B. -B
    Ryde, Felix
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    McGlynn, Sinéad
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Zhang, B.
    Preece, R. D.
    Kouveliotou, C.
    The Connection Between Thermal and Non-Thermal Emission in Gamma-ray Bursts: General considerations and GRB090902B as a Case Study2011Inngår i: GAMMA RAY BURSTS 2010. American Institute of Physics Conference Series, 2011, Vol. 1358, s. 91-94Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Photospheric (thermal) emission is inherent to the gamma-ray burst (GRB) “fireball” model. We show that inclusion of this component in the analysis of the GRB prompt emission phase naturally explains some of the prompt GRB spectra seen by the Fermi satellite over its entire energy band. The sub-MeV peak is explained as multi-color black body emission, and the high energy tail, extending up to the GeV band, results from roughly similar contributions of synchrotron emission, synchrotron self Compton (SSC) and Comptonization of the thermal photons by energetic electrons originating after dissipation of the kinetic energy above the photosphere. We briefly discuss the theory of multicolor black body emission from relativistically expanding plasma, before showing how the analysis method proposed results in a complete, self consistent picture of the physical conditions at both emission sites of the thermal and non-thermal radiation. Furthermore, it enables to extract the values of the free model parameters. We demonstrate the analysis method on GRB090902B, and present the values of the physical parameters deduced. We briefly discuss the uniqueness of GRB090902B-type spectra.

  • 1554. Pe'er, Asaf
    et al.
    Barlow, Hugh
    O'Mahony, Shane
    Margutti, Raffaella
    Ryde, Felix
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik. Oskar Klein Ctr Cosmoparticle Phys, Sweden.
    Larsson, Josefin
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik. Oskar Klein Ctr Cosmoparticle Phys, Sweden.
    Lazzati, Davide
    Livio, Mario
    HYDRODYNAMIC PROPERTIES of GAMMA-RAY BURST OUTFLOWS DEDUCED from the THERMAL COMPONENT2015Inngår i: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 813, nr 2, artikkel-id 127Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We study the properties of a significant thermal emission component that was identified in 47 gamma-ray bursts observed by different instruments. Within the framework of the "fireball" model, we deduce the values of the Lorentz factor Gamma, and the acceleration radius, r(0), for these bursts. We find that all the values of Gamma in our sample are in the range 10(2) <= Gamma <= 10(3), with <Gamma > = 370. We find a very weak dependence of Gamma on the acceleration radius r0, Gamma proportional to r(0)(alpha) with alpha - -0.10 +/- 0.09 at the sigma - 2.1 confidence level. The values of r(0) span a wide range, 10(6.5) <= r(0) <= 10(9.5) cm, with a mean value of < r(0)> similar to 10(8) cm. This is higher than the gravitational radius of a 10 M-circle dot black hole by a factor of approximate to 30. We argue that this result provides indirect evidence for jet propagation inside a massive star, and suggests the existence of recollimation shocks that take place close to this radius.

  • 1555. Pe'er, Asaf
    et al.
    Ryde, Felix
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    A THEORY OF MULTICOLOR BLACKBODY EMISSION FROM RELATIVISTICALLY EXPANDING PLASMAS2011Inngår i: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 732, nr 1, s. 49-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We consider the emission of photons from the inner parts of a relativistically expanding plasma outflow, characterized by a constant Lorentz factor, Gamma. Photons that are injected in regions of high optical depth are advected with the flow until they escape at the photosphere. Due to multiple scattering below the photosphere, the locally emerging comoving photon distribution is thermal. However, as an observer simultaneously sees photons emitted from different angles, hence with different Doppler boosting, the observed spectrum is a multicolor blackbody. We calculate here the properties of the observed spectrum at different observed times. Due to the strong dependence of the photospheric radius on the angle to the line of sight, for parameters characterizing gamma-ray bursts (GRBs) thermal photons are seen up to tens of seconds following the termination of the inner engine. At late times, following the inner engine termination, both the number flux and energy flux of the thermal spectrum decay as F proportional to t(-2). At these times, the multicolor blackbody emission results in a power law at low energies (below the thermal peak), with power-law index F-nu proportional to nu(0). We discuss the implications and limitations of this result in the study of GRBs.

  • 1556. Pe'er, Asaf
    et al.
    Ryde, Felix
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Wijers, Ralph A. M. J.
    Meszaros, Peter
    Rees, Martin J.
    A new method of determining the initial size and Lorentz factor of gamma-ray burst fireballs using a thermal emission component2007Inngår i: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 664, nr 1, s. L1-L4Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In recent years, increasing evidence has emerged for a thermal component in the gamma- and X- ray spectrum of the prompt emission phase in gamma- ray bursts. The temperature and flux of the thermal component show a characteristic break in the temporal behavior after a few seconds. We show here that measurements of the temperature and flux of the thermal component at early times ( before the break) allow the determination of the values of two of the least restricted fireball model parameters: the size at the base of the flow and the outflow bulk Lorentz factor. Relying on the thermal emission component only, this measurement is insensitive to the inherent uncertainties of previous estimates of the bulk motion Lorentz factor. We give specific examples of the use of this method: for GRB 970828 at redshift z = 0.9578, we show that the physical size at the base of the flow is r(0) = (2.9 +/- 1.8) x 10(8) Y-0(-3/2) cm and the Lorentz factor of the flow is Gamma = (305 +/- 28) Y-0(1/4), and for GRB 990510 at z= 1.619, r(0) = (1.7 +/- 1.7) x 10(8)Y(0)(-3/2) cm and Gamma = (384 +/- 71)y(0)(1/4), where Y= 1Y(0) is the between the total fireball energy and the energy emitted in g- rays.

  • 1557.
    Perepelitsa, Dennis, V
    et al.
    Univ Colorado, Boulder, CO 80309 USA..
    Jensen, Bengt
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Ohm, Christian
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Ripellino, Giulia
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik. Royal Inst Technol, Phys Dept, Stockholm, Sweden..
    Sidebo, P. Edvin
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Strandberg, Jonas
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Zwalinski, L.
    CERN, Geneva, Switzerland..
    Photon-tagged measurements of jet quenching with ATLAS2019Inngår i: Nuclear Physics A, ISSN 0375-9474, E-ISSN 1873-1554, Vol. 982, s. 595-598Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Events containing a high transverse momentum (p(T)) prompt photon offer a useful way to study the dynamics of the hot, dense medium produced in heavy ion collisions. Because photons do not carry color charge, they are unaffected by the medium, and thus provide information about the momentum, direction, and flavor (quark or gluon) of the associated hard-scattered parton before it begins to shower and become quenched. In particular, the presence of a high-p(T) photon can be used to select pp and Pb+Pb events with the same configuration before quenching, limiting the effects of quenching-induced selection biases present in other jet measurements. The large statistics pp and Pb+Pb data delivered by the LHC in 2015 allow for a detailed study of photon-tagged jet quenching effects, such as the overall parton energy loss and modified structure of the component of the shower which remains correlated with the initial parton direction (e.g. in cone). In this proceeding, photon-tagged measurements of jet quenching by ATLAS are reported.

  • 1558. Periale, L.
    et al.
    Peskov, V.
    Iacobaeus, C.
    Francke, T.
    Lund-Jensen, Bengt
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Pavlopoulos, P.
    Picchi, P.
    Pietropaolo, F.
    Tokanai, F.
    The successful operation of hole-type gaseous detectors at cryogenic temperatures2005Inngår i: IEEE Transactions on Nuclear Science, ISSN 0018-9499, E-ISSN 1558-1578, Vol. 52, nr 4, s. 927-931Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We have demonstrated that hole-type gaseous detectors, gas electron multipliers and capillary plates (CPs) can operate at temperatures down to 77 K. For example, a single CP can operate at gains above 10(3) in the entire temperature interval between 77 and 300 K. The same CP combined with CsI photocathodes operates perfectly well at gains of 100-1000, depending on the gas mixture. The obtained results open new fields of applications for CPs as detectors of ultraviolet light and charged particles at cryogenic temperatures: liquid noble gas time-projection chambers, detectors for weakly interacting massive particles or liquid Xe scintillating calorimeters, and cryogenic positron-emission tomography.

  • 1559. Periale, L.
    et al.
    Peskov, V.
    Iacobaeus, C.
    Lund-Jensen, Bengt
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Pavlopoulos, P.
    Picchi, P.
    Pietropaolo, F.
    A study of the operation of especially designed photosensitive gaseous detectors at cryogenic temperatures2006Inngår i: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, ISSN 0168-9002, E-ISSN 1872-9576, Vol. 567, nr 1, s. 381-385Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In some experiments and applications there is need for large-area photosensitive detectors to operate at cryogenic temperatures. Nowadays, vacuum PMs are usually used for this purpose. We have developed special designs of planar photosensitive gaseous detectors able to operate at cryogenic temperatures. Such detectors are much cheaper than PMs and are almost insensitive to magnetic fields. Results of systematic measurements of their quantum efficiencies, the maximum achievable gains and long-term stabilities will be presented. The successful operation of these detectors open realistic possibilities in replacing PMs by photosensitive gaseous detectors in some applications dealing with cryogenic liquids; for example in experiments using noble liquid TPCs or noble liquid scintillating calorimeters.

  • 1560. Periale, L.
    et al.
    Peskov, V.
    Iacobaeus, C.
    Lund-Jensen, Bengt
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Picchi, P.
    Pietropaolo, F.
    Rodionov, I.
    Photosensitive gaseous detectors for cryogenic temperature applications2007Inngår i: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, ISSN 0168-9002, E-ISSN 1872-9576, Vol. 573, nr 1-2, s. 302-305Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    There are several proposals and projects today for building LXe time projection chambers (TPCs) for dark matter search. Important elements of these TPCs are the photomultipliers operating either inside LXe or in vapours above the liquid. We have recently demonstrated that photosensitive gaseous detectors (wire type and hole type) can operate perfectly well, until temperatures of LN2. In this paper, results of systematic studies of operation of the photosensitive version of these detectors (combined with reflective or semi-transparent CsI photocathodes) in the temperature interval of 300-150K are presented. In particular, it was demonstrated that both sealed and flushed by a gas detectors could operate at a quite stable fashion in a year/time scale. Obtained results strongly indicate that they can be cheap and simple alternatives to photomultipliers or avalanche solid-state detectors in LXe TPC applications.

  • 1561.
    Pernow, Marcus
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Phenomenology of SO(10) Grand Unified Theories2019Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Although the Standard Model (SM) of particle physics describes observations well, there are several shortcomings of it. The most crucial of these are that the SM cannot explain the origin of neutrino masses and the existence of dark matter. Furthermore, there are several aspects of it that are seemingly ad hoc, such as the choice of gauge group and the cancellation of gauge anomalies.

    These shortcomings point to a theory beyond the SM. Although there are many proposed models for physics beyond the SM, in this thesis, we focus on grand unified theories based on the SO(10) gauge group. It predicts that the three gauge groups in the SM unify at a higher energy into one, which contains the SM as a subgroup. We focus on the Yukawa sector of these models and investigate the extent to which the observables such as fermion masses and mixing parameters can be accommodated into different models based on the SO(10) gauge group. Neutrino masses and leptonic mixing parameters are particularly interesting, since SO(10) models naturally embed the seesaw mechanism.

    The difference in energy scale between the electroweak scale and the scale of unification spans around 14 orders of magnitude. Therefore, one must relate the parameters of the SO(10) model to those of the SM through renormalization group equations. We investigate this for several different models by performing fits of SO(10) models to fermion masses and mixing parameters, taking into account thresholds at which heavy right-handed neutrinos are integrated out of the theory. Although the results are in general dependent on the particular model under consideration, there are some general results that appear to hold true. The observ- ables of the Yukawa sector can in general be accommodated into SO(10) models only if the neutrino masses are normally ordered and that inverted ordering is strongly disfavored. We find that the observable that provides the most tension in the fits is the leptonic mixing angle θ2l3, whose value is consistently favored to be lower in the fits than the actual value. Furthermore, we find that numerical fits to the data favor type-I seesaw over type-II seesaw for the generation of neutrino masses.

  • 1562. Perot, B.
    et al.
    Carasco, C.
    Bernard, S.
    Mariani, A.
    Szabo, J. L.
    Sannie, G.
    Valkovic, V.
    Sudac, D.
    Viesti, G.
    Lunardon, M.
    Botosso, C.
    Nebbia, G.
    Pesente, S.
    Moretto, S.
    Zenoni, A.
    Donzella, A.
    Moszynski, M.
    Gierlik, M.
    Klamra, Wlodzimierz
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Le Tourneur, P.
    Lhuissier, M.
    Colonna, A.
    Tintori, C.
    Peerani, P.
    Sequeira, V.
    Salvato, M.
    Measurement of 14 MeV neutron-induced prompt gamma-ray spectra from 15 elements found in cargo containers2008Inngår i: Applied Radiation and Isotopes, ISSN 0969-8043, E-ISSN 1872-9800, Vol. 66, nr 4, s. 421-434Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Within the EURopean Illicit TRAfficking Countermeasures Kit (EURITRACK) project, the gamma-ray spectra produced in a series of materials by 14-MeV tagged-neutron beams have been collected in the inspection portal equipped with large volume Nal(Tl) detectors, in order to build a database of signatures for various elements: C, N, O, Na, Al, Si, Cl, K, Ca, Cr, Fe, Ni, Cu, Zn, Pb. The measured spectra have been compared with prediction from Monte Carlo simulations to verify the consistency of the relevant nuclear data inputs. This library of measured 14-MeV neutron-induced gamma-ray spectra is currently used in a data processing algorithm to unfold the energy spectra of the transported goods into elementary contributions, thus allowing material identification.

  • 1563. Perot, B.
    et al.
    Carasco, C.
    Klamra, Wlodzimierz
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Isaksson, P.
    Le Tourneur, P.
    Lhuissier, M.
    Colonna, A.
    Tintori, C.
    Peerani, P.
    Sequeira, V.
    Salvato, M.
    et al,
    Development of the EURITRACK tagged neutron inspection system2007Inngår i: Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, ISSN 0168-583X, E-ISSN 1872-9584, Vol. 261, nr 02-jan, s. 295-298Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The EURopean Illicit TRAfficing Countermeasures Kit (EURITRACK) project is part of the 6th European Union Framework Program. It aims at developing a Tagged Neutron Inspection System (TNIS) to detect illicit materials, such as explosives and narcotics, in cargo containers. Fast neutron induced reactions produce specific gamma-rays used to determine the chemical composition of the inspected material. The associated particle technique is employed to precisely locate the interaction points of the neutrons. A new deuterium-tritium neutron generator has been developed, including a pixelized alpha particle detector. The TNIS also comprises high-efficiency fast neutron and gamma-ray detectors, a dedicated front-end electronics and an integrated software to entirely drive the system and automatically process the data. Most components have been integrated during last months at Institute Ruder Boskovic, in Zagreb, Croatia. An overview of the TNIS and of its preliminary performances is presented.

  • 1564. Peskov, V.
    et al.
    Baibussinov, B.
    Centro, S.
    Di Mauro, A.
    Lund-Jensen, Bengt
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Martinengo, P.
    Nappi, E.
    Oliveira, R.
    Pietropaolo, F.
    Picchi, P.
    Periale, L.
    Rodionov, I.
    Ventura, S.
    Development and first tests of GEM-Like detectors with resistive electrodes2007Inngår i: IEEE Transactions on Nuclear Science, ISSN 0018-9499, E-ISSN 1558-1578, Vol. 54, nr 5, s. 1784-1791Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We have developed and tested several prototypes of GEM-like detectors with electrodes coated with resistive layers or completely made of resistive materials. These detectors can operate stably at gains close to 10(5). The resistive layers limit the energy of discharges appearing at higher gains thus making the detectors very robust. We demonstrated that the cathodes of some of these detectors could be coated by CsI or SbCs layers to enhance the detection efficiency for the UV and visible photons. We also discovered that such detectors can operate stably in the cascade mode and high overall gains (similar to 10(6)) are reachable. Applications in several areas, for example in RICH or in noble liquid TPCs are therefore possible. The first results from the detection of UV photons at room and cryogenic temperatures will be given.

  • 1565. Petrosian, V.
    et al.
    Bouvier, A.
    Ryde, Felix
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Gamma-Ray Bursts as Cosmological Tools2009Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In recent years there has been considerable activity in using gamma-ray bursts as cosmological probes for determining global cosmological parameters complementing results from type Ia supernovae and other methods. This requires a characteristics of the source to be a standard candle. We show that contrary to earlier indications the accumulated data speak against this possibility. Another method would be to use correlation between a distance dependent and a distance independent variable to measure distance and determine cosmological parameters as is done using Cepheid variables and to some extent Type Ia supernovae. Many papers have dealt with the use of so called Amati relation, first predicted by Lloyd, Petrosian and Mallozzi, or the Ghirlanda relation for this purpose. We have argued that these procedure involve many unjustified assumptions which if not true could invalidate the results. In particular, we point out that many evolutionary effects can affect the final outcome. In particular, we demonstrate that the existing data from Swift and other earlier satellites show that the gamma-ray burst may have undergone luminosity evolution. Similar evolution may be present for other variables such as the peak photon energy of the total radiated energy. Another out come of our analysis is determination of the luminosity function and the comoving rate evolution of gamma-ray bursts which does not seem to agree with the cosmic star formation rate. We caution however, that the above result are preliminary and includes primarily the effect of detection threshold. Other selection effects, perhaps less important than this, are also known to be present and must be accounted for. We intend to address these issues in future publications.

  • 1566.
    Pettersson, Nora
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Study of systematic effects from the level of Final State Radiation in tt-background to SUSY dilepton channels2011Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Uncertainties in radiative effects of the quarks in -background in the form of final state radiation (FSR) are significant when it comes to reducing all forms of systematics that can arise from measuring the jets energy. Analysis on FSR is in general conducted on different simulated samples where one has included the radiative effect using algorithms such as PYTHIA[29]. The hypothesis is that through the re-weighting of the -background nominal sample one could add a better representation of the FSR effect. Finding a simple way to include a better description of FSR would not only save time in the simulation process but it would also be a way to reduce the systematic errors originating from limited MC statistics. Due to statistical effects coming from the simulations one cannot use the basic approach to define the effect of FSR as simply the difference between nominal and FSR. Two methods are tested to estimate the FSR effects; the first method uses a set of efficiency factors to represent the signal regions, the second method is to add a weight to the events of the nominal sample. The first method show positive results, especially in SR2, compared to a basic analysis, with an uncertainty of the FSR effect of: SR1:±29% SR2: ±51% SR3: ±37%. While a basic analysis gave an uncertainty of ±42%, ±122% and 36%. The second method shows positive signs where the re-weighted sample moves closer to the behaviour of the FSR sample. However, both methods are based on insufficient amount of statistics to draw any absolute conclusions.

  • 1567. Picozza, P.
    et al.
    Carlson, Per
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Pearce, Mark
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Rossetto, Laura
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    et, al,
    Cosmic ray study with the PAMELA experiment2013Inngår i: Journal of Physics, Conference Series, ISSN 1742-6588, E-ISSN 1742-6596, Vol. 409, nr 1Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In six years of data collection years in space, the experiment PAMELA has discovered very interesting features in cosmic rays, namely in the fluxes of protons, helium, electrons, that might change our basic vision of the mechanisms of production, acceleration and propagation of cosmic rays in the Galaxy. In addition, PAMELA measurements of cosmic antiproton and positron fluxes are setting strong constraints to the nature of Dark Matter. The continuous particle detection is allowing a constant monitoring of the solar activity and detailed study of the solar modulation for a long period, giving important improvements to the comprehension of the heliosphere mechanisms. PAMELA is also measuring the radiation environment around the Earth, and has recently discovered an antiproton radiation belt.

  • 1568. Picozza, P.
    et al.
    Galper, A. M.
    Castellini, G.
    Lund, J.
    Lundquist, J.
    Pearce, Mark
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Zverev, V. G.
    et al,
    PAMELA - A payload for antimatter matter exploration and light-nuclei astrophysics2007Inngår i: Astroparticle physics, ISSN 0927-6505, E-ISSN 1873-2852, Vol. 27, nr 4, s. 296-315Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The PAMELA experiment is a satellite-borne apparatus designed to study charged particles in the cosmic radiation with a particular focus on antiparticles. PAMELA is mounted on the Resurs DK1 satellite that was launched from the Baikonur cosmodrome on June 15th 2006. The PAMELA apparatus comprises a time-of-flight system, a magnetic spectrometer, a silicon-tungsten electromagnetic calorimeter, an anticoincidence system, a shower tail catcher scintillator and a neutron detector. The combination of these devices allows antiparticles to be reliably identified from a large background of other charged particles. This paper reviewsthe design, space qualification and on-ground performance of PAMELA. The in-orbit performance will be discussed in future publications.

  • 1569. Picozza, P.
    et al.
    Marcelli, L.
    Adriani, O.
    Barbarino, G. C.
    Bazilevskaya, G. A.
    Bellotti, R.
    Boezio, M.
    Bogomolov, E. A.
    Bonechi, L.
    Bongi, M.
    Bonvicini, V.
    Bottai, S.
    Bruno, A.
    Cafagna, F.
    Campana, D.
    Carlson, P.
    Casolino, M.
    Castellini, G.
    de Pascale, M. P.
    de Rosa, G.
    de Simone, N.
    di Felice, V.
    Galper, A. M.
    Grishantseva, L.
    Hofverberg, Petter
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Leonov, A.
    Koldashov, S. V.
    Krutkov, S. Y.
    Kvashnin, A. N.
    Malvezzi, V.
    Menn, W.
    Mikhailov, V. V.
    Mocchiutti, E.
    Orsi, Silvio
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Osteria, G.
    Papini, P.
    Pearce, Mark
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Ricci, M.
    Ricciarini, S. B.
    Simon, M.
    Sparvoli, R.
    Spillantini, P.
    Stozhkov, Y. I.
    Vacchi, A.
    Vannuccini, E.
    Vasilyev, G.
    Voronov, S. A.
    Yurkin, Y. T.
    Zampa, G.
    Zampa, N.
    Zverev, V. G.
    Dark Matter Research and the PAMELA Space Mission2009Inngår i: SOURCES AND DETECTION OF DARK MATTER AND DARK ENERGY IN THE UNIVERSE / [ed] Cline, DB, 2009, Vol. 1166, s. 141-150Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    On the 15th of June 2006, the PAMELA satellite-borne experiment was launched from the Bajkonur cosmodrome and since July 2006 it has been collected data. The core of the apparatus is a silicon-microstrip magnetic spectrometer combined with a time-of-flight system, a silicon-tungsten electromagnetic calorimeter, an anticoincidence system, a shower tail counter scintillator and a neutron detector. The overall devices allow precision studies of the charged cosmic radiation to be conducted over a wide energy range (100 MeV - 100's GeV) with high statistics. The primary scientific goal is the measurement of the antiproton and positron energy spectra in order to search for exotic sources, such as dark matter particle annihilation. PAMELA is also searching for primordial antinuclei ((He) over bar). Concomitant, but not secondary, goals are the measurements of light nuclei and their isotopes for studying the energy dependence of cosmic ray lifetimes in the Galaxy, the monitoring of the solar activity and the study of the radiation belts.

  • 1570. Picozza, P.
    et al.
    Sparvoli, R.
    Adriani, O.
    Barbarino, G.
    Bazilevskaya, G. A.
    Bellotti, R.
    Boezio, M.
    Bogomolov, E. A.
    Bonechi, L.
    Bongi, M.
    Bonvicini, V.
    Borisov, S.
    Bottai, S.
    Bruno, A.
    Cafagna, F.
    Campana, D.
    Carbone, R.
    Carlson, Per
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Casolino, M.
    Castellini, G.
    Consiglio, L.
    De Pascale, M. P.
    De Santis, C.
    De Simone, N.
    Di Felice, V.
    Galper, A. M.
    Gillard, William
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Grishantseva, L.
    Jerse, G.
    Karelin, A.
    Koldashov, S. V.
    Krutkov, S. Y.
    Kvashnin, A. N.
    Leonov, A.
    Malvezzi, V.
    Marcelli, L.
    Menn, W.
    Mikhailov, V. V.
    Mocchiutti, E.
    Monaco, A.
    Mori, N.
    Nikonov, N.
    Osteria, G.
    Papini, P.
    Pearce, Mark
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Pizzolotto, C.
    Ricci, M.
    Ricciarini, S. B.
    Rossetto, Laura
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Simon, M.
    Spillantini, P.
    Stozhkov, Y. I.
    Vacchi, A.
    Vannuccini, E.
    Vasilyev, G.
    Voronov, S. A.
    Wu, J.
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Yurkin, Y. T.
    Zampa, G.
    Zampa, N.
    Zverev, V. G.
    Cosmic ray studies with PAMELA experiment2011Inngår i: Proceedings of the 14th Lomonosov Conference on Elementary Particle Physics: Particle Physics at the Year of Astronomy: Dedicated to the Late Academician Alexey Sissakian, 2011, s. 200-206Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The instrument PAMELA, in orbit since June 15th, 2006 on board of the Russian satellite Resurs DK1, is daily delivering to ground 16 Gigabytes of data. The apparatus is designed to study charged particles in the cosmic radiation, with a particular focus on antiparticles for searching antimatter and signals of dark matter annihilation. A combination of a magnetic spectrometer and different detectors allows antiparticles to be reliably identified from a large background of other charged particles. New results on the antiproton-to-proton and positron-toall electron ratios over a wideenergy range (1-100 GeV) have been obtained from the PAMELA mission. These data are mainly interpreted in terms of dark matter annihilation or pulsar contribution.

  • 1571. Pletsch, H. J.
    et al.
    Guillemot, L.
    Fehrmann, H.
    Allen, B.
    Kramer, M.
    Aulbert, C.
    Ackermann, M.
    Ajello, M.
    de Angelis, A.
    Atwood, W. B.
    Baldini, L.
    Ballet, J.
    Barbiellini, G.
    Bastieri, D.
    Bechtol, K.
    Bellazzini, R.
    Borgland, A. W.
    Bottacini, E.
    Brandt, T. J.
    Bregeon, J.
    Brigida, M.
    Bruel, P.
    Buehler, R.
    Buson, S.
    Caliandro, G. A.
    Cameron, R. A.
    Caraveo, P. A.
    Casandjian, J. M.
    Cecchi, C.
    Celik, Oe
    Charles, E.
    Chaves, R. C. G.
    Cheung, C. C.
    Chiang, J.
    Ciprini, S.
    Claus, R.
    Cohen-Tanugi, J.
    Conrad, J.
    Cutini, S.
    D'Ammando, F.
    Dermer, C. D.
    Digel, S. W.
    Drell, P. S.
    Drlica-Wagner, A.
    Dubois, R.
    Dumora, D.
    Favuzzi, C.
    Ferrara, E. C.
    Franckowiak, A.
    Fukazawa, Y.
    Fusco, P.
    Gargano, F.
    Gehrels, N.
    Germani, S.
    Giglietto, N.
    Giordano, F.
    Giroletti, M.
    Godfrey, G.
    Grenier, I. A.
    Grondin, M. -H
    Grove, J. E.
    Guiriec, S.
    Hadasch, D.
    Hanabata, Y.
    Harding, A. K.
    den Hartog, P. R.
    Hayashida, M.
    Hays, E.
    Hill, A. B.
    Hou, X.
    Hughes, R. E.
    Johannesson, G.
    Jackson, Miranda S.
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Jogler, T.
    Johnson, A. S.
    Johnson, W. N.
    Kataoka, J.
    Kerr, M.
    Knoedlseder, J.
    Kuss, M.
    Lande, J.
    Larsson, S.
    Latronico, L.
    Lemoine-Goumard, M.
    Longo, F.
    Loparco, F.
    Lovellette, M. N.
    Lubrano, P.
    Massaro, F.
    Mayer, M.
    Mazziotta, M. N.
    McEnery, J. E.
    Mehault, J.
    Michelson, P. F.
    Mitthumsiri, W.
    Mizuno, T.
    Monzani, M. E.
    Morselli, A.
    Moskalenko, I. V.
    Murgia, S.
    Nakamori, T.
    Nemmen, R.
    Nuss, E.
    Ohno, M.
    Ohsugi, T.
    Omodei, N.
    Orienti, M.
    Orlando, E.
    de Palma, F.
    Paneque, D.
    Perkins, J. S.
    Piron, F.
    Pivato, G.
    Porter, T. A.
    Raino, S.
    Rando, R.
    Ray, P. S.
    Razzano, M.
    Reimer, A.
    Reimer, O.
    Reposeur, T.
    Ritz, S.
    Romani, R. W.
    Romoli, C.
    Sanchez, D. A.
    Parkinson, P. M. Saz
    Schulz, A.
    Sgro, C.
    do Couto e Silva, E.
    Siskind, E. J.
    Smith, D. A.
    Spandre, G.
    Spinelli, P.
    Suson, D. J.
    Takahashi, H.
    Tanaka, T.
    Thayer, J. B.
    Thayer, J. G.
    Thompson, D. J.
    Tibaldo, L.
    Tinivella, M.
    Troja, E.
    Usher, T. L.
    Vandenbroucke, J.
    Vasileiou, V.
    Vianello, G.
    Vitale, V.
    Waite, A. P.
    Winer, B. L.
    Wood, K. S.
    Wood, M.
    Yang, Z.
    Zimmer, S.
    Binary Millisecond Pulsar Discovery via Gamma-Ray Pulsations2012Inngår i: Science, ISSN 0036-8075, E-ISSN 1095-9203, Vol. 338, nr 6112, s. 1314-1317Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Millisecond pulsars, old neutron stars spun up by accreting matter from a companion star, can reach high rotation rates of hundreds of revolutions per second. Until now, all such "recycled" rotation-powered pulsars have been detected by their spin-modulated radio emission. In a computing-intensive blind search of gamma-ray data from the Fermi Large Area Telescope (with partial constraints from optical data), we detected a 2.5-millisecond pulsar, PSR J1311-3430. This unambiguously explains a formerly unidentified gamma-ray source that had been a decade-long enigma, confirming previous conjectures. The pulsar is in a circular orbit with an orbital period of only 93 minutes, the shortest of any spin-powered pulsar binary ever found.

  • 1572.
    Poulain, M.
    et al.
    Univ Innsbruck, Inst Astro & Teilchenphys, Technikerstr 25-8, A-6020 Innsbruck, Austria..
    Paolillo, M.
    Univ Napoli Federico II, Dept Phys, Via Cinthia 9, I-80126 Naples, Italy.;Ist Nazl Fis Nucl, Sez Napoli, Via Cinthia 9, I-80126 Naples, Italy.;INAF, Osservatorio Astron Capodimonte, Via Moiariello 16, I-80131 Naples, Italy..
    De Cicco, D.
    Univ Napoli Federico II, Dept Phys, Via Cinthia 9, I-80126 Naples, Italy.;Millennium Inst Astrophys MAS, Nuncio Monsenor Sotero Sanz 100, Santiago, Chile.;Pontificia Univ Catolica Chile, Inst Astrofis, Av Vicuna Mackenna 4860, Santiago 7820436, Spain..
    Brandt, W. N.
    Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA.;Penn State Univ, Inst Gravitat & Cosmos, University Pk, PA 16802 USA..
    Bauer, F. E.
    Millennium Inst Astrophys MAS, Nuncio Monsenor Sotero Sanz 100, Santiago, Chile.;Pontificia Univ Catolica Chile, Inst Astrofis, Av Vicuna Mackenna 4860, Santiago 7820436, Spain.;Space Sci Inst, 4750 Walnut St,Suite 2015, Boulder, CO 80301 USA..
    Falocco, Serena
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Vagnetti, F.
    Univ Roma Tor Vergata, Dept Phys, Via Ric Sci 1, I-00133 Rome, Italy..
    Grado, A.
    INAF, Osservatorio Astron Capodimonte, Via Moiariello 16, I-80131 Naples, Italy..
    Ragosta, F.
    Univ Napoli Federico II, Dept Phys, Via Cinthia 9, I-80126 Naples, Italy.;Ist Nazl Fis Nucl, Sez Napoli, Via Cinthia 9, I-80126 Naples, Italy.;INAF, Osservatorio Astron Capodimonte, Via Moiariello 16, I-80131 Naples, Italy..
    Botticella, M. T.
    INAF, Osservatorio Astron Capodimonte, Via Moiariello 16, I-80131 Naples, Italy..
    Cappellaro, E.
    INAF, Osservatorio Astron Capodimonte, Via Moiariello 16, I-80131 Naples, Italy..
    Pignata, G.
    Millennium Inst Astrophys MAS, Nuncio Monsenor Sotero Sanz 100, Santiago, Chile.;Univ Andres Bello, Dept Ciencias Fis, Avda Republ 252, Santiago, Chile..
    Vaccari, M.
    Univ Western Cape, Dept Phys & Astron, Private Bag X17, ZA-7535 Cape Town, South Africa.;INAF, Ist Radioastron, Via Gobetti 101, I-40129 Bologna, Italy..
    Schipani, P.
    INAF, Osservatorio Astron Capodimonte, Via Moiariello 16, I-80131 Naples, Italy..
    Covone, G.
    Univ Napoli Federico II, Dept Phys, Via Cinthia 9, I-80126 Naples, Italy.;Ist Nazl Fis Nucl, Sez Napoli, Via Cinthia 9, I-80126 Naples, Italy..
    Longo, G.
    Univ Napoli Federico II, Dept Phys, Via Cinthia 9, I-80126 Naples, Italy.;Ist Nazl Fis Nucl, Sez Napoli, Via Cinthia 9, I-80126 Naples, Italy.;INAF, Osservatorio Astron Capodimonte, Via Moiariello 16, I-80131 Naples, Italy..
    Napolitano, N. R.
    Sun Yat Sen Univ, Sch Phys & Astron, Zhuhai Campus, Guangzhou 519082, Peoples R China..
    Extending the variability selection of active galactic nuclei in the W-CDF-S and SERVS/SWIRE region2020Inngår i: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 634Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Context. Variability has proven to be a powerful tool to detect active galactic nuclei (AGN) in multi-epoch surveys. The new-generation facilities expected to become operational in the next few years will mark a new era in time-domain astronomy and their wide-field multi-epoch campaigns will favor extensive variability studies.Aims. We present our analysis of AGN variability in the second half of the VST survey of the Wide Chandra Deep Field South, performed in the r band and covering a 2 sq. deg area. The analysis complements a previous work, in which the first half of the area was investigated. We provide a reliable catalog of variable AGN candidates, which will be critical targets in future variability studies.Methods. We selected a sample of optically variable sources and made use of infrared data from the Spitzer mission to validate their nature by means of color-based diagnostics.Results. We obtain a sample of 782 AGN candidates among which 12 are classified as supernovae, 54 as stars, and 232 as AGN. We estimate a contamination less than or similar to 20% and a completeness similar to 38% with respect to mid-infrared selected samples.

  • 1573. Preece, R.
    et al.
    Burgess, J. Michael
    University of Alabama in Huntsville, United States.
    von Kienlin, A.
    Bhat, P. N.
    Briggs, M. S.
    Byrne, D.
    Chaplin, V.
    Cleveland, W.
    Collazzi, A. C.
    Connaughton, V.
    Diekmann, A.
    Fitzpatrick, G.
    Foley, S.
    Gibby, M.
    Giles, M.
    Goldstein, A.
    Greiner, J.
    Gruber, D.
    Jenke, P.
    Kippen, R. M.
    Kouveliotou, C.
    McBreen, S.
    Meegan, C.
    Paciesas, W. S.
    Pelassa, V.
    Tierney, D.
    van der Horst, A. J.
    Wilson-Hodge, C.
    Xiong, S.
    Younes, G.
    Yu, H. -F
    Ackermann, M.
    Ajello, M.
    Axelsson, Magnus
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Baldini, L.
    Barbiellini, G.
    Baring, M. G.
    Bastieri, D.
    Bellazzini, R.
    Bissaldi, E.
    Bonamente, E.
    Bregeon, J.
    Brigida, M.
    Bruel, P.
    Buehler, R.
    Buson, S.
    Caliandro, G. A.
    Cameron, R. A.
    Caraveo, P. A.
    Cecchi, C.
    Charles, E.
    Chekhtman, A.
    Chiang, J.
    Chiaro, G.
    Ciprini, S.
    Claus, R.
    Cohen-Tanugi, J.
    Cominsky, L. R.
    Conrad, J.
    D'Ammando, F.
    de Angelis, A.
    de Palma, F.
    Dermer, C. D.
    Desiante, R.
    Digel, S. W.
    Di Venere, L.
    Drell, P. S.
    Drlica-Wagner, A.
    Favuzzi, C.
    Franckowiak, A.
    Fukazawa, Y.
    Fusco, P.
    Gargano, F.
    Gehrels, N.
    Germani, S.
    Giglietto, N.
    Giordano, F.
    Giroletti, M.
    Godfrey, G.
    Granot, J.
    Grenier, I. A.
    Guiriec, S.
    Hadasch, D.
    Hanabata, Y.
    Harding, A. K.
    Hayashida, M.
    Iyyani, S.
    Jogler, T.
    Joannesson, G.
    Kawano, T.
    Knoedlseder, J.
    Kocevski, D.
    Kuss, M.
    Lande, J.
    Larsson, Josefin
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Larsson, S.
    Latronico, L.
    Longo, F.
    Loparco, F.
    Lovellette, M. N.
    Lubrano, P.
    Mayer, M.
    Mazziotta, M. N.
    Michelson, P. F.
    Mizuno, T.
    Monzani, M. E.
    Moretti, Elena
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Morselli, A.
    Murgia, S.
    Nemmen, R.
    Nuss, E.
    Nymark, Tanja
    KTH, Skolan för teknikvetenskap (SCI), Fysik.
    Ohno, M.
    Ohsugi, T.
    Okumura, A.
    Omodei, N.
    Orienti, M.
    Paneque, D.
    Perkins, J. S.
    Pesce-Rollins, M.
    Piron, F.
    Pivato, G.
    Porter, T. A.
    Racusin, J. L.
    Raino, S.
    Rando, R.
    Razzano, M.
    Razzaque, S.
    Reimer, A.
    Reimer, O.
    Ritz, S.
    Roth, M.
    Ryde, Felix
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Sartori, A.
    Scargle, J. D.
    Schulz, A.
    Sgro, C.
    Siskind, E. J.
    Spandre, G.
    Spinelli, P.
    Suson, D. J.
    Tajima, H.
    Takahashi, H.
    Thayer, J. G.
    Thayer, J. B.
    Tibaldo, L.
    Tinivella, M.
    Torres, D. F.
    Tosti, G.
    Troja, E.
    Usher, T. L.
    Vandenbroucke, J.
    Vasileiou, V.
    Vianello, G.
    Vitale, V.
    Werner, M.
    Winer, B. L.
    Wood, K. S.
    Zhu, S.
    The First Pulse of the Extremely Bright GRB 130427A: A Test Lab for Synchrotron Shocks2014Inngår i: Science, ISSN 0036-8075, E-ISSN 1095-9203, Vol. 343, nr 6166, s. 51-54Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Gamma-ray burst (GRB) 130427A is one of the most energetic GRBs ever observed. The initial pulse up to 2.5 seconds is possibly the brightest well-isolated pulse observed to date. A fine time resolution spectral analysis shows power-law decays of the peak energy from the onset of the pulse, consistent with models of internal synchrotron shock pulses. However, a strongly correlated power-law behavior is observed between the luminosity and the spectral peak energy that is inconsistent with curvature effects arising in the relativistic outflow. It is difficult for any of the existing models to account for all of the observed spectral and temporal behaviors simultaneously.

  • 1574. Procter, M. G.
    et al.
    Cullen, D. M.
    Taylor, M. J.
    Pakarinen, J.
    Auranen, K.
    Bäck, Torbjörn
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Braunroth, T.
    Cederwall, Bo
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Dewald, A.
    Grahn, T.
    Greenlees, P. T.
    Jakobsson, U.
    Julin, R.
    Juutinen, S.
    Herzan, A.
    Konki, J.
    Leino, M.
    Liotta, Roberto
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Partanen, J.
    Peura, P.
    Rahkila, P.
    Ruotsalainen, P.
    Sandelius, M.
    Saren, J.
    Scholey, C.
    Sorri, J.
    Stolze, S.
    Uusitalo, J.
    Qi, Chong
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Isomer-tagged differential-plunger measurements in Xe-113(54)2013Inngår i: Physical Review C. Nuclear Physics, ISSN 0556-2813, E-ISSN 1089-490X, Vol. 87, nr 1, s. 014308-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The 278-keV M2 gamma decay from the vh(11/2) isomeric state in Xe-113 has been observed for the first time using the recoil-isomer tagging technique. The half-life of the isomer has been measured to be 6.9(3) mu s. The derived B(M2) value is in agreement with the trend of systematic measurements of M2 transition strengths in neutron-deficient tellurium and tin isotopes. The lifetime of the first excited state in the vh(11/2) band has been measured using the recoil distance Doppler-shift method. The extracted B(E2) value has been compared to theoretical CD-Bonn calculations and recent lifetime measurements in Te-109. This comparison of B(E2) values has been used to shed light on the possible influence of collective degrees of freedom on M2 transition strengths in the most neutron-deficient xenon nuclei. The vh(11/2) band is deduced to have a degree of deformation comparable with the ground-state bands of the even-mass xenon isotopes. However, the value deduced in this work indicates a loss of collective behavior when compared with the lower-mass Te-109. This result suggests that, while changes in deformation may be partly responsible for the observed trend in B(M2) values for increasing Z, other effects may also be present.

  • 1575.
    Puri, Akshat
    et al.
    Univ Illinois, Champaign, IL 61820 USA..
    Jensen, Bengt
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik. Royal Inst Technol, Phys Dept, Stockholm, Sweden..
    Ohm, Christian
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik. Royal Inst Technol, Phys Dept, Stockholm, Sweden..
    Ripellino, Giulia
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik. Royal Inst Technol, Phys Dept, Stockholm, Sweden..
    Sidebo, P. Edvin
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Strandberg, Jonas
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Zwalinski, L.
    CERN, Geneva, Switzerland..
    Measurement of angular and momentum distributions of charged particles within and around jets in Pb plus Pb and pp collisions at root s(NN)=5.02 TeV with ATLAS at the LHC2019Inngår i: Nuclear Physics A, ISSN 0375-9474, E-ISSN 1873-1554, Vol. 982, s. 177-179Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Studies of the fragmentation of jets into charged particles in heavy-ion collisions can help in understanding the mechanism of jet quenching by the hot and dense QCD matter created in such collisions, the quark-gluon plasma. These proceedings present a measurement of the angular distribution of charged particles around the jet axis in root s(NN) = 5.02 TeV Pb+Pb and pp collisions, done using the ATLAS detector at the LHC. The measurement is performed inside jets reconstructed with the anti-k(t) algorithm with radius parameter R = 0.4, and is extended to regions outside the jet cone. Results are presented as a function of Pb+Pb collision centrality, and both jet and charged-particle transverse momenta.

  • 1576.
    Qi, Chong
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Andreyev, A.
    University of the West of Scotland.
    Huyse, M.
    K.U. Leuven.
    Liotta, Roberto
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Van Duppen, P.
    K.U. Leuven.
    Wyss, Ramon
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Suppression of alpha formation probability around the N = 126 shell closure2011Inngår i: Frontiers In Nuclear Structure, Astrophysics, And Reactions (FINUSTAR 3), 2011, Vol. 1377, s. 296-300Konferansepaper (Fagfellevurdert)
    Abstract [en]

    alpha formation amplitudes extracted from experimental data are presented and an abrupt change around the N = 126 shell closure is noted. It is explained as a sudden hindrance of the clustering of nucleons. The clustering induced by the pairing mode acting upon the four nucleons is inhibited if the configuration space does not allow a proper manifestation of the pairing collectivity.

  • 1577.
    Qi, Chong
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Andreyev, A. N.
    Huyse, M.
    Liotta, Roberto
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Van Duppen, P.
    Wyss, Ramon A.
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Abrupt changes in alpha-decay systematics as a manifestation of collective nuclear modes2010Inngår i: Physical Review C. Nuclear Physics, ISSN 0556-2813, E-ISSN 1089-490X, Vol. 81, nr 6, s. 064319-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An abrupt change in alpha-decay systematics around the N = 126 neutron shell closure is discussed. It is explained as a sudden hindrance of the clustering of the nucleons that eventually form the a particle. This is because the clustering induced by the pairing mode acting upon the four nucleons is inhibited if the configuration space does not allow a proper manifestation of the pairing collectivity.

  • 1578.
    Qi, Chong
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Blomqvist, Jan
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Bäck, Torbjörn
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Cederwall, Bo
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Johnson, Arne
    KTH, Skolan för teknikvetenskap (SCI), Fysik.
    Liotta, Roberto
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Wyss, Ramon
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Coherence features of the spin-aligned neutron-proton pair coupling scheme2012Inngår i: Physica scripta. T, ISSN 0281-1847, Vol. T150, s. 014031-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The seniority scheme has been shown to be extremely useful for the classification of nuclear states in semi-magic nuclei. The neutron-proton (np) correlation breaks the seniority symmetry in a major way. As a result, the corresponding wave function is a mixture of many components with different seniority quantum numbers. In this paper, we show that the np interaction may favor a new kind of coupling in N = Z nuclei, i.e. the so-called isoscalar spin-aligned np pair mode. Shell model calculations reveal that the ground and low-lying yrast states of the N = Z nuclei Pd-92 and Cd-96 may be mainly built upon such spin-aligned np pairs, each carrying the maximum angular momentum J = 9 allowed by the shell 0 g(9/2) which is dominant in this nuclear region.

  • 1579.
    Qi, Chong
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Blomqvist, Jan
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Bäck, Torbjörn
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Cederwall, Bo
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Johnson, Arne
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Liotta, Roberto
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Wyss, Ramon
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Spin-aligned neutron-proton pair mode in atomic nuclei2011Inngår i: Physical Review C. Nuclear Physics, ISSN 0556-2813, E-ISSN 1089-490X, Vol. 84, nr 2, s. 021301-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Shell-model calculations using realistic interactions reveal that the ground and low-lying yrast states of the N = Z nucleus (92)(46)Pd are mainly built upon isoscalar neutron-proton pairs, each carrying the maximum angular momentum J = 9 allowed by the shell 0g(9/2), which is dominant in this nuclear region. This structure is different from that found in the ground and low-lying yrast states of all other even-even nuclei studied so far. The low-lying spectrum of excited states generated by such correlated neutron-proton pairs has two distinctive features: (i) the levels are almost equidistant at low energies and (ii) the transition probability I -> I - 2 is approximately constant and strongly selective. This unique mode is shown to replace normal isovector pairing as the dominant coupling scheme in N = Z nuclei approaching the doubly magic nucleus (100)Sn.

  • 1580.
    Qi, Chong
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Delion, Doru S.
    Liotta, Roberto J.
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Wyss, Ramon
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Effects of formation properties in one-proton radioactivity2012Inngår i: Physical Review C. Nuclear Physics, ISSN 0556-2813, E-ISSN 1089-490X, Vol. 85, nr 1, s. 011303-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    It is shown that the proton formation probability, extracted from experimental data corresponding to one-proton radioactivity, is divided into two regions when plotted as a function of an universal parameter. This parameter is derived from a microscopic description of the decay process. In this way we explain the systematics of proton emission half-lives. At the same time the formation probability is shown to be a useful quantity to determine the deformation property of the mother nucleus.

  • 1581.
    Qi, Chong
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Liotta, Roberto
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Wyss, Ramon
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Competition of different coupling schemes in atomic nuclei2012Inngår i: Advanced Many-Body And Statistical Methods In Mesoscopic Systems, Institute of Physics Publishing (IOPP), 2012, Vol. 338, nr 012027, s. 012027-Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Shell model calculations reveal that the ground and low-lying yrast states of the N = Z nuclei Pd-92(46) and Cd-96 are mainly built upon isoscalar spin - aligned neutron - proton pairs each carrying the maximum angular momentum J = 9 allowed by the shell 0g(9)/(2) which is dominant in this nuclear region. This mode of excitation is unique in nuclei and indicates that the spin - aligned pair has to be considered as an essential building block in nuclear structure calculations. In this contribution we will discuss this neutron - proton pair coupling scheme in detail. In particular, we will explore the competition between the normal monopole pair coupling and the spin - aligned coupling schemes. Such a coupling may be useful in elucidating the structure properties of N = Z and neighboring nuclei.

  • 1582.
    Qi, Chong
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Liotta, Roberto
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Wyss, Ramon
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Spin-aligned neutron-proton pair coupling in the era of large scale computing2012Inngår i: Journal of Physics, Conference Series, ISSN 1742-6588, E-ISSN 1742-6596, Vol. 381, nr 1, s. 012106-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Shell model calculations reveal that the ground and low-lying yrast states of the N = Z nuclei Pd-92(46) and Cd-96(48) are mainly built upon isoscalar spin-aligned neutron-proton pairs each carrying the maximum angular momentum J = 9 allowed by the shell 0g(9/2) which is dominant in this nuclear region. This mode of excitation is unique in nuclei and indicates that the spin-aligned pair has to be considered as an essential building block in nuclear structure calculations. In this contribution we will discuss this neutron-proton pair coupling scheme in detail. It may help in understanding the intrinsic structure of the shell-model wave function. In particular, we will explore the competition between the normal monopole pair coupling and the spin-aligned coupling schemes.

  • 1583.
    Qi, Chong
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Xu, F. R.
    Liotta, Roberto J.
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Wyss, Ramon
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Zhang, M. Y.
    Asawatangtrakuldee, C.
    Hu, D.
    Microscopic mechanism of charged-particle radioactivity and generalization of the Geiger-Nuttall law2009Inngår i: Physical Review C. Nuclear Physics, ISSN 0556-2813, E-ISSN 1089-490X, Vol. 80, nr 4, s. 044326-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A linear relation for charged-particle emissions is presented starting from the microscopic mechanism of the radioactive decay. It relates the logarithms of the decay half-lives with two variables, called. chi' and. rho', which depend upon the Q values of the outgoing clusters as well as the masses and charges of the nuclei involved in the decay. This relation explains well all known cluster decays. It is found to be a generalization of the Geiger-Nuttall law in a radioactivity, and therefore we call it the universal decay law. Predictions of the most likely emissions of various clusters are presented by applying the law over the whole nuclear chart. It is seen that the decays of heavier clusters with nonequal proton and neutron numbers are mostly located in the trans-lead region. The emissions of clusters with equal protons and neutrons, like C-12 and O-16, are possible in some neutron-deficient nuclei with Z >= 54.

  • 1584.
    Qi, Chong
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Xu, Zhen Xiang
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Liotta, Roberto J.
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Analytic proof of partial conservation of seniority in j=9/2 shells2012Inngår i: Nuclear Physics A, ISSN 0375-9474, E-ISSN 1873-1554, Vol. 884, s. 21-35Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A partial conservation of the seniority quantum number in j = 9/2 shells has been found recently in a numerical application. In this paper an analytic proof for this problem is derived as an extension of the work [L. Zamick, P. Van Isacker, Phys. Rev. C 78 (2008) 044327]. We analyze the properties of the non-diagonal interaction matrix elements with the help of the one-particle and two-particle coefficients of fractional parentage (cfp's). It is found that all non-diagonal (and the relevant diagonal) matrix elements can be re-expressed in simple ways and are proportional to certain one-particle cfp's. This remarkable occurrence of partial dynamic symmetry is the consequence of the peculiar property of the j = 9/2 shell, where all it = 3 and 5 states are uniquely defined.

  • 1585. Racusin, J. L.
    et al.
    Burns, E.
    Goldstein, A.
    Connaughton, V.
    Wilson-Hodge, C. A.
    Jenke, P.
    Blackburn, L.
    Briggs, M. S.
    Broida, J.
    Camp, J.
    Christensen, N.
    Hui, C. M.
    Littenberg, T.
    Shawhan, P.
    Singer, L.
    Veitch, J.
    Bhat, P. N.
    Cleveland, W.
    Fitzpatrick, G.
    Gibby, M. H.
    von Kienlin, A.
    McBreen, S.
    Mailyan, B.
    Meegan, C. A.
    Paciesas, W. S.
    Preece, R. D.
    Roberts, O. J.
    Stanbro, M.
    Veres, P.
    Zhang, B. -B
    Ackermann, M.
    Albert, A.
    Atwood, W. B.
    Axelsson, M.
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Baldini, L.
    Ballet, J.
    Barbiellini, G.
    Baring, M. G.
    Bastieri, D.
    Bellazzini, R.
    Bissaldi, E.
    Blandford, R. D.
    Bloom, E. D.
    Bonino, R.
    Bregeon, J.
    Bruel, P.
    Buson, S.
    Caliandro, G. A.
    Cameron, R. A.
    Caputo, R.
    Caragiulo, M.
    Caraveo, P. A.
    Cavazzuti, E.
    Charles, E.
    Chiang, J.
    Ciprini, S.
    Costanza, F.
    Cuoco, A.
    Cutini, S.
    D'Ammando, F.
    de Palma, F.
    Desiante, R.
    Digel, S. W.
    Di Lalla, N.
    Di Mauro, M.
    Di Venere, L.
    Drell, P. S.
    Favuzzi, C.
    Ferrara, E. C.
    Focke, W. B.
    Fukazawa, Y.
    Funk, S.
    Fusco, P.
    Gargano, F.
    Gasparrini, D.
    Giglietto, N.
    Gill, R.
    Giroletti, M.
    Glanzman, T.
    Granot, J.
    Green, D.
    Grove, J. E.
    Guillemot, L.
    Guiriec, S.
    Harding, A. K.
    Jogler, T.
    Johannesson, G.
    Kamae, T.
    Kensei, S.
    Kocevski, D.
    Kuss, M.
    Larsson, Stefan
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Latronico, L.
    Li, J.
    Longo, F.
    Loparco, F.
    Lubrano, P.
    Magill, J. D.
    Maldera, S.
    Malyshev, D.
    Mazziotta, M. N.
    McEnery, J. E.
    Michelson, P. F.
    Mizuno, T.
    Monzani, M. E.
    Morselli, A.
    Moskalenko, I. V.
    Negro, M.
    Nuss, E.
    Omodei, N.
    Orienti, M.
    Orlando, E.
    Ormes, J. F.
    Paneque, D.
    Perkins, J. S.
    Pesce-Rollins, M.
    Piron, F.
    Pivato, G.
    Porter, T. A.
    Principe, G.
    Raino, S.
    Rando, R.
    Razzano, M.
    Razzaque, S.
    Reimer, A.
    Reimer, O.
    Parkinson, P. M. Saz
    Scargle, J. D.
    Sgro, C.
    Simone, D.
    Siskind, E. J.
    Smith, D. A.
    Spada, F.
    Spinelli, P.
    Suson, D. J.
    Tajima, H.
    Thayer, J. B.
    Torres, D. F.
    Troja, E.
    Uchiyama, Y.
    Vianello, G.
    Wood, K. S.
    Wood, M.
    SEARCHING THE GAMMA-RAY SKY FOR COUNTERPARTS TO GRAVITATIONAL WAVE SOURCES: FERMI GAMMA-RAY BURST MONITOR. AND LARGE AREA TELESCOPE OBSERVATIONS OF LVT151012 AND GW1512262017Inngår i: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 835, nr 1, artikkel-id 82Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We present the Fermi Gamma-ray Burst Monitor (GBM) and Large Area Telescope (LAT) observations of the LIGO binary black hole merger event GW151226 and candidate LVT151012. At the time of the LIGO triggers on LVT151012 and GW151226, GBM was observing 68% and 83% of the localization regions, and LAT was observing 47% and 32%, respectively. No candidate electromagnetic counterparts were detected by either the GBM or LAT. We present a detailed analysis of the GBM and LAT data over a range of timescales from seconds to years, using automated pipelines and new techniques for characterizing the flux upper bounds across large areas of the sky. Due to the partial GBM and LAT coverage of the large LIGO localization regions at the trigger times for both events, differences in source distances and masses, as well as the uncertain degree to which emission from these sources could be beamed, these non-detections cannot be used to constrain the variety of theoretical models recently applied to explain the candidate GBM counterpart to GW150914.

  • 1586.
    Radhika, D.
    et al.
    Dayananda Sagar Univ, Dept Phys, Bangalore 560068, Karnataka, India..
    Sreehari, H.
    ISRO Satellite Ctr, Space Astron Grp, SSIF ISITE Campus,Outer Ring Rd, Bangalore 560037, Karnataka, India.;Indian Inst Sci, Bangalore 560012, Karnataka, India..
    Nandi, A.
    ISRO Satellite Ctr, Space Astron Grp, SSIF ISITE Campus,Outer Ring Rd, Bangalore 560037, Karnataka, India..
    Iyer, Nirmal
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik. Albanova Univ Ctr, KTH PAP, S-10691 Stockholm, Sweden..
    Mandal, S.
    Indian Inst Space Sci & Technol, Thiruvananthapuram, Kerala, India..
    Broad-band spectral evolution and temporal variability of IGR J17091-3624 during its 2016 outburst: SWIFT and NuSTAR results2018Inngår i: Astrophysics and Space Science, ISSN 0004-640X, E-ISSN 1572-946X, Vol. 363, nr 9, artikkel-id 189Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We report on the 2016 outburst of the transient Galactic Black Hole candidate IGR J17091-3624 based on the observation campaign carried out with SWIFT and NuSTAR. The outburst profile, as observed with SWIFT-XRT, shows a typical 'q'-shape in the Hardness Intensity Diagram (HID). Based on the spectral and temporal evolution of the different parameters, we are able to identify all the spectral states in the q-profile of HID and the Hardness-RMS diagram (HRD). Both XRT and NuSTAR observations show an evolution of low frequency Quasi periodic oscillations (QPOs) during the low hard and hard intermediate states of the outburst rising phase. We also find mHz QPOs along-with distinct coherent class variabilities (heartbeat oscillations) with different timescales, similar to the -class (observed in GRS 1915+105). Phenomenological modelling of the broad-band XRT and NuSTAR spectra also reveals the evolution of high energy cut-off and presence of reflection from ionized material during the rising phase of the outburst. Further, we conduct the modelling of X-ray spectra of SWIFT and NuSTAR in 0.5-79 keV to understand the accretion flow dynamics based on two component flow model. From this modelling, we constrain the mass of the source to be in the range of with 90% confidence, which is consistent with earlier findings.

  • 1587. Ricci, M.
    et al.
    de Nolfo, G. A.
    Martucci, M.
    Ryan, J. M.
    Boezio, M.
    Bravar, U.
    Carbone, R.
    Christian, E. R.
    Mergè, M.
    Mocchiutti, E.
    Munini, R.
    Stochaj, S.
    Thakur, N.
    Adriani, O.
    Barbarino, G. C.
    Bazilevskaya, G. A.
    Bellotti, R.
    Bogomolov, E. A.
    Bongi, M.
    Bonvicini, V.
    Bottai, S.
    Bruno, A.
    Cafagna, F.
    Campana, D.
    Carlson, Per
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Casolino, M.
    Castellini, G.
    Donato, C. D. E.
    de Pascale, M. P.
    Santis, C. D. E.
    Simone, N. D. E.
    Felice, V. D. I.
    Formato, V.
    Galper, A. M.
    Karelin, A. V.
    Koldashov, S. V.
    Koldobskiy, S.
    Krutkov, Y.
    Kvashnin, A. N.
    Leonov, A.
    Malakhov, V.
    Marcelli, L.
    Mayorov, A. G.
    Menn, W.
    Mikhailov, V. V.
    Monaco, A.
    Mori, N.
    Osteria, G.
    Palma, F.
    Papini, P.
    Pearce, M.
    Picozza, P.
    Pizzolotto, C.
    Ricciarini, S. B.
    Sarkar, R.
    Scotti, V.
    Simon, M.
    Sotgiu, A.
    Sparvoli, R.
    Spillantini, P.
    Stozhkov, Y. I.
    Vacchi, A.
    Vannuccini, E.
    Vasilyev, G.
    Voronov, S. A.
    Yurkin, Y. T.
    Zampa, G.
    Zampa, N.
    Zverev, V. G.
    Study on 2012 march 7 solar particle event and forbush decrease with the PAMELA experiment2013Inngår i: Proceedings of the 33rd International Cosmic Rays Conference, ICRC 2013, Sociedade Brasileira de Fisica , 2013Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The PAMELA (Payload for Antimatter Matter Exploration and Light-nuclei Astro-physics) space-borne experiment was launched on 15 June 2006 and has been continuously collecting data since then. The apparatus measures electrons, positrons, protons, anti-protons and heavier nuclei from about 100 MeV to several hundreds of GeV. The on-board instrumentation is built around a permanent magnet with a silicon microstrip tracker, providing charge and track detection information. During solar maximum conditions of solar cycle 24, PAMELA has been providing key information about solar energetic particles (SEPs) and their influence at Earth. We discuss here the recent 2012 March 7 SEP event with a brief comment on the subsequent Forbush decrease, registered by PAMELA. This event was also observed by Fermi/LAT exhibiting unprecedented time-extended γ-ray emission (> 100 MeV) lasting nearly 20 hours. We compare the derived accelerated ion population at the Sun with the ion population measured in space by PAMELA and discuss the implications for particle acceleration. 

  • 1588. Ricci, M.
    et al.
    Pizzella, G.
    Martucci, M.
    Bruno, A.
    Di Felice, V.
    Marcelli, N.
    Adriani, O.
    Barbarino, G. C.
    Bazilevskaya, G. A.
    Bellotti, R.
    Boezio, M.
    Bogomolov, E. A.
    Bongi, M.
    Bonvicini, V.
    Cafagna, F.
    Campana, D.
    Carlson, Per
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Casolino, M.
    Castellini, G.
    De Santis, C.
    Galper, A. M.
    Karelin, A. V.
    Koldashov, S. V.
    Koldobskiy, S.
    Krutkov, S. Y.
    Kvashnin, A. N.
    Leonov, A.
    Malakhov, V.
    Marcelli, L.
    Mayorov, A. G.
    Menn, W.
    Mergè, M.
    Mikhailov, V. V.
    Mocchiutti, E.
    Monaco, A.
    Mori, N.
    Munini, R.
    Osteria, G.
    Panico, B.
    Papini, P.
    Pearce, Mark
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Picozza, P.
    Ricciarini, S. B.
    Simon, M.
    Sparvoli, R.
    Spillantini, P.
    Stozhkov, Y. I.
    Vacchi, A.
    Vannuccini, E.
    Vasilyev, G.
    Voronov, S. A.
    Yurkin, Y. T.
    Zampa, G.
    Zampa, N.
    Effect of the Jupiter magnetosphere on the cosmic ray protons measured with the PAMELA experiment2017Inngår i: Proceedings of Science, Sissa Medialab Srl , 2017Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The very intense Jovian magnetic field produces a magnetosphere where high-energy charged particles are trapped, allowing the possibility for acceleration mechanism that could inject those particles in the open space. In the last decades, accelerated electrons from the Jupiter magnetosphere have been detected and studied in the interplanetary space.This work investigated whether the proton data obtained by the PAMELA space-borne detector between July 9th, 2006 to August 31th, 2014 shows signatures that arise from Jupiter. In this proceeding the basis of the analysis of cosmic ray protons by PAMELA are described and results will be shown at the conference. 

  • 1589. Ricciarini, S. B.
    et al.
    Adriani, O.
    Barbarino, G. C.
    Bazilevskaya, G. A.
    Bellotti, R.
    Boezio, M.
    Bogomolov, E. A.
    Bongi, M.
    Bonvicini, V.
    Bottai, S.
    Bruno, A.
    Cafagna, F.
    Campana, D.
    Carbone, R.
    Carlson, P.
    KTH, Skolan för teknikvetenskap (SCI), Fysik.
    Casolino, M.
    Castellini, G.
    De Donato, C.
    De Pascale, M. P.
    De Santis, C.
    De Simone, N.
    Di Felice, V.
    Formato, V.
    Galper, A. M.
    Karelin, A. V.
    Kheymits, M. D.
    Koldashov, S. V.
    Koldobskiy, S.
    Krutkov, S. Y.
    Kvashnin, A. N.
    Leonov, A.
    Malakhov, V.
    Marcelli, L.
    Martucci, M.
    Mayorov, A. G.
    Menn, W.
    Mergè, M.
    Mikhailov, V. V.
    Mocchiutti, E.
    Monaco, A.
    Mori, N.
    Munini, R.
    Osteria, G.
    Palma, F.
    Panico, B.
    Papini, P.
    Pearce, Mark
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Picozza, P.
    Pizzolotto, C.
    Ricci, M.
    Sarkar, R.
    Simon, M.
    Scotti, V.
    Sparvoli, R.
    Spillantini, P.
    Stozhkov, Y. I.
    Vacchi, A.
    Vannuccini, E.
    Vasilyev, G. I.
    Voronov, S. A.
    Yurkin, Y. T.
    Zampa, G.
    Zampa, N.
    Zverev, V. G.
    PAMELA mission: Heralding a new era in cosmic ray physics2014Inngår i: EPJ Web of Conferences, 2014Konferansepaper (Fagfellevurdert)
    Abstract [en]

    After seven years of data taking in space, the experiment PAMELA is showing very interesting features in cosmic rays, namely in the fluxes of protons, helium, electrons, that might change our basic vision of the mechanisms of production, acceleration and propagation of cosmic rays in the galaxy. In addition, PAMELA measurements of cosmic antiproton and positron fluxes are setting strong constraints to the nature of Dark Matter. The continuous particle detection is allowing a constant monitoring of the solar activity and detailed study of the solar modulation for a long period, giving important improvements to the comprehension of the heliosphere mechanisms. PAMELA is also measuring the radiation environment around the Earth, and has recently discovered an antiproton radiation belt.

  • 1590.
    Ripellino, Giulia
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    A search for supersymmetry in events containing a leptonically decaying Z boson, jets and missing transverse momentum in √ s = 13 TeV pp collisions with the ATLAS detector2016Inngår i: Proceedings of Science, Proceedings of Science (PoS) , 2016Konferansepaper (Fagfellevurdert)
    Abstract [en]

    A search for supersymmetric particles in final states characterized by a leptonically decaying Z boson, missing transverse momentum and jets is presented. The analysis uses proton-proton collision data collected by the ATLAS detector at a center-of-mass energy √ s = 13 TeV corresponding to a total integrated luminosity of 3.2 fb-1. An excess of events above the Standard Model expectation, with a significance of 2.2σ, is observed.

  • 1591.
    Ripellino, Giulia
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    A search for Supersymmetry in final states with two same-flavor opposite-sign leptons, jets and missing transverse momentum with the ATLAS detector2017Licentiatavhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    This thesis presents a search for Supersymmetry in final states containing two same-flavor opposite-sign leptons, jets and large missing transverse momentum. The search makes use of 36.1 fb−1 of proton-proton collision data collected at a center-of-mass energy of √s = 13 TeV by the ATLAS detector at the Large Hadron Collider. Two signal scenarios, which both involve the pair-production of squarks or gluinos decaying into final states with two leptons and the lightest supersymmetric particle, are targeted by the analysis. The first scenario considers decay chains with a leptonically decaying Z boson and is characterized by a peak in the dilepton invariant mass distribution. In the second scenario, decays through intermediate sleptons or an off-shell Z boson are considered. Such processes lead to a kinematic endpoint in the dilepton invariant mass distribution. The main Standard Model backgrounds include the pair-production of top quarks and direct production of Z bosons. These backgrounds are estimated with two data-driven methods. The observed data is found to be consistent with the Standard Model expectation and the results are interpreted in simplified Supersymmetry models for gluino and squark pair-production. Sensitivity is provided for gluino and squark masses up to 1.85 TeV and 1.3 TeV respectively. 

  • 1592.
    Ripellino, Giulia
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    The alignment of the ATLAS inner detector in run 22016Inngår i: Proceedings of Science, Proceedings of Science (PoS) , 2016, Vol. Part F128560Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The ATLAS reconstruction of charged particle trajectories relies on the Inner Detector tracking system. The accuracy of the reconstruction is limited by the finite resolution of the detector elements and the imperfect knowledge about their positions. A precise alignment of the detector is therefore essential. Here, the strategy and the status of the Inner Detector alignment in ATLAS during the LHC Run 2 are presented and the alignment challenges related to the distortion of the new innermost Pixel layer, the IBL, are discussed.

  • 1593.
    Romazanov, J.
    et al.
    Forschungszentrum Julich, Inst Energie & Klimaforsch, Plasmaphys, Partner Trilateral Euregio Cluster TEC, D-5242 Julich, Germany.;Forschungszentrum Julich GmbH, Inst Energie & Klimaforsch Plasmaphys, D-52425 Julich, Germany..
    Bergsåker, Henrik
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Elektroteknik, Fusionsplasmafysik.
    Bykov, Igor
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Elektroteknik, Fusionsplasmafysik.
    Frassinetti, Lorenzo
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Elektroteknik, Fusionsplasmafysik.
    Garcia Carrasco, Alvaro
    KTH, Skolan för elektro- och systemteknik (EES), Fusionsplasmafysik.
    Hellsten, Torbjörn
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Elektroteknik, Fusionsplasmafysik.
    Johnson, Thomas
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Elektroteknik, Fusionsplasmafysik.
    Menmuir, S.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Elektroteknik, Fusionsplasmafysik.
    Petersson, P
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Elektroteknik, Fusionsplasmafysik.
    Rachlew, Elisabeth
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Ratynskaia, Svetlana
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Elektroteknik, Rymd- och plasmafysik.
    Rubel, Marek
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Elektroteknik, Fusionsplasmafysik.
    Stefániková, Estera
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Elektroteknik, Fusionsplasmafysik.
    Ström, Petter
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Elektroteknik, Fusionsplasmafysik.
    Tholerus, Emmi
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Elektroteknik, Fusionsplasmafysik.
    Tolias, Panagiotis
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Elektroteknik, Rymd- och plasmafysik.
    Olivares, Pablo Vallejos
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Elektroteknik, Fusionsplasmafysik.
    Weckmann, Armin
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Elektroteknik, Fusionsplasmafysik.
    Zhou, Y
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Elektroteknik, Fusionsplasmafysik.
    Zychor, I.
    Natl Ctr Nucl Res, PL-05400 Otwock, Poland..
    et al,
    Beryllium global erosion and deposition at JET-ILW simulated with ERO2.02019Inngår i: Nuclear Materials and Energy, E-ISSN 2352-1791, Vol. 18, s. 331-338Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The recently developed Monte-Carlo code ERO2.0 is applied to the modelling of limited and diverted discharges at JET with the ITER-like wall (ILW). The global beryllium (Be) erosion and deposition is simulated and compared to experimental results from passive spectroscopy. For the limiter configuration, it is demonstrated that Be self-sputtering is an important contributor (at least 35%) to the Be erosion. Taking this contribution into account, the ERO2.0 modelling confirms previous evidence that high deuterium (D) surface concentrations of up to similar to 50% atomic fraction provide a reasonable estimate of Be erosion in plasma-wetted areas. For the divertor configuration, it is shown that drifts can have a high impact on the scrape-off layer plasma flows, which in turn affect global Be transport by entrainment and lead to increased migration into the inner divertor. The modelling of the effective erosion yield for different operational phases (ohmic, L- and H-mode) agrees with experimental values within a factor of two, and confirms that the effective erosion yield decreases with increasing heating power and confinement.

  • 1594.
    Rosetto, Laura
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Studies of positron identication with the PAMELA calorimeter2010Licentiatavhandling, monografi (Annet vitenskapelig)
  • 1595.
    Rossetto, Laura
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    PAMELA measurements of high energy cosmic ray positrons2012Doktoravhandling, monografi (Annet vitenskapelig)
  • 1596.
    Rossetto, Laura
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Positron identification study with the PAMELA calorimeter2011Inngår i: Proceedings of ICRC2011, Beijing: ICRC , 2011, s. 31-34Konferansepaper (Fagfellevurdert)
    Abstract [en]

    PAMELA is a satellite-borne experiment which is taking data since 2006. It consists of a permanent magnetic spectrometer, an electromagnetic calorimeter, a time-of-flight system, a neutron detector and an anticoincidence system.

    Positrons are a probe of the local galactic environment, allowing secondary production and propagation models to be tested. Exotic processes such as dark matter particle annihilations may also produce an excess of positrons at high energies. Combining information from different detectors and in particular from the calorimeter, positrons can be identified from the overwhelming proton background. The anomalous positron fraction measured by the PAMELA Collaboration in 2009 [1] covers an energy range up to 100 GeV. A new approach for positron identification is described, based on a combination of shower profile variables in the calorimeter, with the aim of extending the positron fraction analysis up to 300 GeV.

  • 1597.
    Rossetto, Laura
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Studies of positron identification with the PAMELA calorimeter2010Licentiatavhandling, monografi (Annet vitenskapelig)
  • 1598.
    Ryde, Felix
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Axelsson, M.
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Zhang, B. B.
    McGlynn, S.
    Pe'er, A.
    Lundman, Christoffer
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Larsson, S.
    Battelino, Milan
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Zhang, B.
    Bissaldi, E.
    Bregeon, J.
    Briggs, M. S.
    Chiang, J.
    de Palma, F.
    Guiriec, S.
    Larsson, J.
    Longo, F.
    McBreen, S.
    Omodei, N.
    Petrosian, V.
    Preece, R.
    van der Horst, A. J.
    IDENTIFICATION AND PROPERTIES OF THE PHOTOSPHERIC EMISSION IN GRB090902B2010Inngår i: ASTROPHYSICAL JOURNAL LETTERS, ISSN 2041-8213, Vol. 709, nr 2, s. L172-L177Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Fermi Gamma-ray Space Telescope observed the bright and long GRB090902B, lying at a redshift of z = 1.822. Together the Large Area Telescope (LAT) and the Gamma-ray Burst Monitor (GBM) cover the spectral range from 8 keV to >300 GeV. Here we show that the prompt burst spectrum is consistent with emission from the jet photosphere combined with nonthermal emission described by a single power law with photon index -1.9. The photosphere gives rise to a strong quasi-blackbody spectrum which is somewhat broader than a single Planck function and has a characteristic temperature of similar to 290 keV. We model the photospheric emission with a multicolor blackbody, and its shape indicates that the photospheric radius increases at higher latitudes. We derive the averaged photospheric radius R-ph = (1.1 +/- 0.3) x 10(12) Y-1/4 cm and the bulk Lorentz factor of the flow, which is found to vary by a factor of 2 and has a maximal value of Gamma = 750 Y-1/4. Here, Y is the ratio between the total fireball energy and the energy emitted in the gamma rays. We find that during the first quarter of the prompt phase the photospheric emission dominates, which explains the delayed onset of the observed flux in the LAT compared to the GBM. We interpret the broadband emission as synchrotron emission at R similar to 4 x 10(15) cm. Our analysis emphasizes the importance of having high temporal resolution when performing spectral analysis on gamma-ray bursts, since there is strong spectral evolution.

  • 1599.
    Ryde, Felix
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Lundman, Christoffer
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik. Columbia University, USA.
    Acuner, Zeynep
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Emission from accelerating jets in gamma-ray bursts: radiation-dominated flows with increasing mass outflow rates2017Inngår i: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 472, nr 2, s. 1897-1906Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We study the narrowest spectra expected from gamma-ray bursts. We present an analytical function for the spectrum that is emitted from the photosphere of a radiation-dominated flow that is under acceleration. This is the narrowest possible spectrum and it differs from a Planck function. We also present numerical spectra from photospheres occurring during the transition into the coasting phase of the flow. Using these spectral models, we reanalyse Fermi observations of GRB 100507 and GRB 101219, which both have been reported to have very narrow spectra. The bursts can be fitted by the spectral models: for GRB 101219 the spectrum is consistent with the photosphere occurring below or close to the saturation radius, while for GRB 100507 the photosphere position relative to the saturation radius can be determined as a function of time. In the latter case, we find that the photosphere initially occurs in the acceleration phase and thereafter transitions into the coasting phase. We also find that this transition occurs at the same time as the change in observed cooling behaviour: the temperature is close to constant before the break and decays after. We argue that such a transition can be explained by an increasing mass outflow rate. Both analysed bursts thus give strong evidence that the jets are (initially) radiation dominated.

  • 1600.
    Ryde, Felix
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Pe'er, Asaf
    QUASI-BLACKBODY COMPONENT AND RADIATIVE EFFICIENCY OF THE PROMPT EMISSION OF GAMMA-RAY BURSTS2009Inngår i: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 702, nr 2, s. 1211-1229Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We perform time-resolved spectroscopy on the prompt emission in gamma-ray bursts (GRBs) and identify a thermal, photospheric component peaking at a temperature of a few hundreds keV. This peak does not necessarily coincide with the broad-band (keV-GeV) power peak. We show that this thermal component exhibits a characteristic temporal behavior. We study a sample of 56 long bursts, all strong enough to allow time-resolved spectroscopy. We analyze the evolution of both the temperature and flux of the thermal component in 49 individual time-resolved pulses, for which the temporal coverage is sufficient, and find that the temperature is nearly constant during the first few seconds, after which it decays as a power law with a sample-averaged index of -0.68. The thermal flux first rises with an averaged power-law index of 0.63 after which it decays with an averaged index of -2. The break times are the same to within errors. We find that the ratio of the observed to the emergent thermal flux typically exhibits a monotoneous power-law increase during the entire pulse as well as during complex bursts. Thermal photons carry a significant fraction (similar to 30% to more than 50%) of the prompt emission energy (in the observed 25-1900 keV energy band), thereby significantly contributing to the high radiative efficiency. Finally, we show here that the thermal emission can be used to study the properties of the photosphere, hence the physical parameters of the GRB fireball.

293031323334 1551 - 1600 of 1688
RefereraExporteraLink til resultatlisten
Permanent link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf