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  • 51.
    Choubey, Sandhya
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Fysik. Harish-Chandra Research Institute, India.
    Dutta, Debajyoti
    Pramanik, Dipyaman
    Imprints of a light sterile neutrino at DUNE, T2HK, and T2HKK2017Inngår i: Physical Review D: covering particles, fields, gravitation, and cosmology, ISSN 2470-0010, E-ISSN 2470-0029, Vol. 96, nr 5, artikkel-id 056026Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We evaluate the impact of sterile neutrino oscillations in the so-called 3 + 1 scenario on the proposed long baseline experiment in USA and Japan. There are two proposals for the Japan experiment which are called T2HK and T2HKK. We show the impact of sterile neutrino oscillation parameters on the expected sensitivity of T2HK and T2HKK to mass hierarchy, CP violation and octant of theta(23) and compare it against that expected in the case of standard oscillations. We add the expected ten years data from DUNE and present the combined expected sensitivity of T2HKK + DUNE to the oscillation parameters. We do a full marginalization over the relevant parameter space and show the effect of the magnitude of the true sterile mixing angles on the physics reach of these experiments. We show that if one assumes that the source of CP violation is the standard CP phase alone in the test case, then it appears that the expected CP violation sensitivity decreases due to sterile neutrinos. However, if we give up this assumption, then the CP sensitivity could go in either direction. The impact on expected octant of theta(23) and mass hierarchy sensitivity is shown to depend on the magnitude of the sterile mixing angles in a nontrivial way.

  • 52.
    Choubey, Sandhya
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Fysik.
    Goswami, Srubabati
    Gupta, Chandan
    Lakshmi, S. M.
    Thakore, Tarak
    Sensitivity to neutrino decay with atmospheric neutrinos at the INO-ICAL detector2018Inngår i: Physical Review D: covering particles, fields, gravitation, and cosmology, ISSN 2470-0010, E-ISSN 2470-0029, Vol. 97, nr 3, artikkel-id 033005Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Sensitivity of the magnetized Iron Calorimeter (ICAL) detector at the proposed India-based Neutrino Observatory (INO) to invisible decay of the mass eigenstate nu(3) using atmospheric neutrinos is explored. A full three-generation analysis including Earth matter effects is performed in a framework with both decay and oscillations. The wide energy range and baselines offered by atmospheric neutrinos are shown to be excellent for constraining the nu(3) lifetime. We find that with an exposure of 500 kton - yr the ICAL atmospheric experiment could constrain the. 3 lifetime to tau(3)/m(3) > 1.51 x 10(-10) s/eV at the 90% C.L. This is 2 orders of magnitude tighter than the bound from MINOS. The effect of invisible decay on the precision measurement of theta(23) and vertical bar Delta m(32)(2)vertical bar is also studied.

  • 53.
    De Jonckheere, Tim
    et al.
    Vrije Univ Brussel, Theoret Nat Kunde, Pl Laan 2, B-1050 Brussels, Belgium.;Int Solvay Inst, Pl Laan 2, B-1050 Brussels, Belgium..
    Lindgren, Jonathan
    KTH, Centra, Nordic Institute for Theoretical Physics NORDITA. Stockholm Univ, Roslagstullsbacken 23, SE-10691 Stockholm, Sweden..
    Entanglement entropy in inhomogeneous quenches in AdS(3)/CFT22018Inngår i: Physical Review D: covering particles, fields, gravitation, and cosmology, ISSN 2470-0010, E-ISSN 2470-0029, Vol. 98, nr 10, artikkel-id 106006Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We compute entanglement entropy and differential entropy in inhomogeneous holographic quenches in AdS(3)/CFT2. The quenches are arbitrarily inhomogeneous and modeled by an infalling shell of massless nonrotating matter where the final state is not dual to a static black hole but rather to a black hole with time-dependent stress-energy tensor modes. We study the entanglement entropy of an interval and differential entropy of a family of intervals analytically when the inhomogeneities have a perturbative amplitude and numerically for nonperturbative inhomogeneities. While we are in principle able to study these quantities for any inhomogeneities, we discuss two concrete examples: an oscillatory quench and a bilocal quench. Both cases display saturation towards a steady state but do not fully thermalize. Depending on the location and size of the interval, the entanglement entropy displays a variety of interesting phenomena such as plateau phases, bumps, and discontinuities in its first derivative with respect to time.

  • 54.
    Edwards, Thomas D. P.
    et al.
    Univ Amsterdam, Inst Theoret Phys Amsterdam, Gravitat Astroparticle Phys Amsterdam GRAPPA, Sci Pk 904, NL-1098 XH Amsterdam, Netherlands.;Univ Amsterdam, Delta Inst Theoret Phys, Sci Pk 904, NL-1098 XH Amsterdam, Netherlands..
    Kavanagh, Bradley J.
    Univ Amsterdam, Inst Theoret Phys Amsterdam, Gravitat Astroparticle Phys Amsterdam GRAPPA, Sci Pk 904, NL-1098 XH Amsterdam, Netherlands.;Univ Amsterdam, Delta Inst Theoret Phys, Sci Pk 904, NL-1098 XH Amsterdam, Netherlands..
    Weniger, Christoph
    Univ Amsterdam, Inst Theoret Phys Amsterdam, Gravitat Astroparticle Phys Amsterdam GRAPPA, Sci Pk 904, NL-1098 XH Amsterdam, Netherlands.;Univ Amsterdam, Delta Inst Theoret Phys, Sci Pk 904, NL-1098 XH Amsterdam, Netherlands..
    Baum, Sebastian
    KTH, Centra, Nordic Institute for Theoretical Physics NORDITA. Stockholm Univ, Dept Phys, Oskar Klein Ctr Cosmoparticle Phys, S-10691 Stockholm, Sweden ; Stockholm Univ, Roslagstullsbacken 23, S-10691 Stockholm, Sweden.
    Drukier, Andrzej K.
    Stockholm Univ, Dept Phys, Oskar Klein Ctr Cosmoparticle Phys, S-10691 Stockholm, Sweden..
    Freese, Katherine
    KTH, Centra, Nordic Institute for Theoretical Physics NORDITA. Stockholm Univ, Dept Phys, Oskar Klein Ctr Cosmoparticle Phys, S-10691 Stockholm, Sweden ; Stockholm Univ, Roslagstullsbacken 23, S-10691 Stockholm, Sweden ; Univ Michigan, Leinweber Ctr Theoret Phys, Ann Arbor, MI 48109 USA.
    Gorski, Maciej
    Natl Ctr Nucl Res, PL-05400 Otwock, Swierk, Poland..
    Stengel, Patrick
    Stockholm Univ, Dept Phys, Oskar Klein Ctr Cosmoparticle Phys, S-10691 Stockholm, Sweden..
    Digging for dark matter: Spectral analysis and discovery potential of paleo-detectors2019Inngår i: Physical Review D: covering particles, fields, gravitation, and cosmology, ISSN 2470-0010, E-ISSN 2470-0029, Vol. 99, nr 4, artikkel-id 043541Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Paleo-detectors are a recently proposed method for the direct detection of dark matter (DM). In such detectors, one would search for the persistent damage features left by DM-nucleus interactions in ancient minerals. Initial sensitivity projections have shown that paleo-detectors could probe much of the remaining weakly interacting massive particle (WIMP) parameter space. In this paper, we improve upon the cut-and-count approach previously used to estimate the sensitivity by performing a full spectral analysis of the background-and DM-induced signal spectra. We consider two scenarios for the systematic errors on the background spectra: (i) systematic errors on the normalization only, and (ii) systematic errors on the shape of the backgrounds. We find that the projected sensitivity is rather robust to imperfect knowledge of the backgrounds. Finally, we study how well the parameters of the true WIMP model could be reconstructed in the hypothetical case of a WIMP discovery.

  • 55.
    Harko, Tiberiu
    et al.
    Babes Bolyai Univ, Dept Phys, Kogalniceanu St, Cluj Napoca 400084, Romania.;Sun Yat Sen Univ, Sch Phys, Guangzhou 510275, Guangdong, Peoples R China.;UCL, Dept Math, Gower St, London W E 6BT, England..
    Koivisto, Tomi S.
    KTH, Centra, Nordic Institute for Theoretical Physics NORDITA. Stockholm Univ, Roslagstullsbacken 23, S-10691 Stockholm, Sweden..
    Lobo, Francisco S. N.
    Univ Lisbon, Fac Ciencias, Inst Astrofis & Ciencias Espaco, Edificio C8, P-1749016 Lisbon, Portugal.;Univ Lisbon, Fac Ciencias, Dept Fis, Edificio C8, P-1749016 Lisbon, Portugal..
    Olmo, Gonzalo J.
    Univ Valencia, CSIC, Ctr Mixto Univ Valencia, Dept Fis Teor, E-46100 Valencia, Spain.;Univ Valencia, CSIC, Ctr Mixto Univ Valencia, IFIC, E-46100 Valencia, Spain.;Univ Fed Paraiba, Dept Fis, BR-58051900 Joao Pessoa, Paraiba, Brazil..
    Rubiera-Garcia, Diego
    Univ Lisbon, Fac Ciencias, Inst Astrofis & Ciencias Espaco, Edificio C8, P-1749016 Lisbon, Portugal..
    Coupling matter in modified Q gravity2018Inngår i: Physical Review D: covering particles, fields, gravitation, and cosmology, ISSN 2470-0010, E-ISSN 2470-0029, Vol. 98, nr 8, artikkel-id 084043Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We present a novel theory of gravity by considering an extension of symmetric teleparallel gravity. This is done by introducing, in the framework of the metric-affine formalism, a new class of theories where the nonmetricity Q is nonminimally coupled to the matter Lagrangian. More specifically, we consider a Lagrangian of the form L similar to f(1)(Q) + f(2)(Q)L-M, where f(1) and f(2) are generic functions of Q, and L-M is the matter Lagrangian. This nonminimal coupling entails the nonconservation of the energy-momentum tensor, and consequently the appearance of an extra force. The formulation of the gravity sector in terms of the Q instead of the curvature may result in subtle improvements of the theory. In the context of nonminimal matter couplings, we are therefore motivated to explore whether the new geometrical formulation in terms of the Q, when implemented also in the matter sector, would allow more universally consistent and viable realizations of the nonminimal coupling. Furthermore, we consider several cosmological applications by presenting the evolution equations and imposing specific functional forms of the functions f(1)(Q) and f(2)(Q), such as power-law and exponential dependencies of the nonminimal couplings. Cosmological solutions are considered in two general classes of models, and found to feature accelerating expansion at late times.

  • 56.
    Huang, Guo-yuan
    et al.
    Chinese Acad Sci, Inst High Energy Phys, Beijing 100049, Peoples R China.;Univ Chinese Acad Sci, Sch Phys Sci, Beijing 100049, Peoples R China..
    Ohlsson, Tommy
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Teoretisk partikelfysik. Univ Iceland, Sci Inst, Dunhaga 3, IS-107 Reykjavik, Iceland..
    Zhou, Shun
    Chinese Acad Sci, Inst High Energy Phys, Beijing 100049, Peoples R China.;Univ Chinese Acad Sci, Sch Phys Sci, Beijing 100049, Peoples R China.;Peking Univ, Ctr High Energy Phys, Beijing 100871, Peoples R China..
    Observational constraints on secret neutrino interactions from big bang nucleosynthesis2018Inngår i: Physical Review D: covering particles, fields, gravitation, and cosmology, ISSN 2470-0010, E-ISSN 2470-0029, Vol. 97, nr 7, artikkel-id 075009Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We investigate possible interactions between neutrinos and massive scalar bosons via g(phi)(nu) over bar nu phi (or massive vector bosons via g(V)(nu) over bar gamma(mu)nu V-mu) and explore the allowed parameter space of the coupling constant g phi (or g(V)) and the scalar (or vector) boson mass m(phi) (or m(V)) by requiring that these secret neutrino interactions (SNIs) should not spoil the success of big bang nucleosynthesis (BBN). Incorporating the SNIs into the evolution of the early Universe in the BBN era, we numerically solve the Boltzmann equations and compare the predictions for the abundances of light elements with observations. It turns out that the constraint on g(phi) and m(phi) in the scalar-boson case is rather weak, due to a small number of degrees of freedom (d.o.f.). However, in the vector-boson case, the most stringent bound on the coupling g(V) less than or similar to 6 x 10(-10) at 95% confidence level is obtained for m(V) similar or equal to 1 MeV, while the bound becomes much weaker g(V) less than or similar to 8 x 10(-6) for smaller masses m(V) less than or similar to 10(-4) MeV. Moreover, we discuss in some detail how the SNIs affect the cosmological evolution and the abundances of the lightest elements.

  • 57.
    Kuhnel, Florian
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Teoretisk partikelfysik. Stockholm Univ, Sweden.
    Freese, Katherine
    Constraints on primordial black holes with extended mass functions2017Inngår i: Physical Review D: covering particles, fields, gravitation, and cosmology, ISSN 2470-0010, E-ISSN 2470-0029, Vol. 95, nr 8, artikkel-id 083508Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Constraints on primordial black holes in the range 10(-18) M circle dot to 10(3) M circle dot are reevaluated for a general class of extended mass functions. Whereas previous work has assumed that PBHs are produced with one single mass, instead there is expected to be a range of masses even in the case of production from a single mechanism; constraints therefore change from previous literature. Although tightly constrained in the majority of cases, it is shown that, even under conservative assumptions, primordial black holes in the mass range 10(-10) M circle dot to 10(-8) M circle dot could still constitute the entirety of the dark matter. This stresses both the importance for a comprehensive reevaluation of all respective constraints that have previously been evaluated only for a monochromatic mass function and the need to obtain more constraints in the allowed mass range.

  • 58.
    Kuhnel, Florian
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Teoretisk partikelfysik. AlbaNova University Center, Sweden.
    Ohlsson, Tommy
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Teoretisk partikelfysik. AlbaNova University Center, Sweden; University of Iceland, Iceland.
    Signatures of compact halos of sterile-neutrino dark matter2017Inngår i: Physical Review D: covering particles, fields, gravitation, and cosmology, ISSN 2470-0010, E-ISSN 2470-0029, Vol. 96, nr 10, artikkel-id 103020Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We investigate compact halos of sterile-neutrino dark matter and examine observable signatures with respect to neutrino and photon emission. Primarily, we consider two cases: primordial black-hole halos and ultracompact minihalos. In both cases, we find that there exists a broad range of possible parameter choices such that detection in the near future with x-ray and gamma-ray telescopes might be well possible. In fact, for energies above 10 TeV, the neutrino telescope IceCube would be a splendid detection machine for such macroscopic dark-matter candidates.

  • 59. Maria Ezquiaga, Jose
    et al.
    Garcia-Bellido, Juan
    Zumalacarregui, Miguel
    KTH, Centra, Nordic Institute for Theoretical Physics NORDITA.
    Field redefinitions in theories beyond Einstein gravity using the language of differential forms2017Inngår i: Physical Review D: covering particles, fields, gravitation, and cosmology, ISSN 2470-0010, E-ISSN 2470-0029, Vol. 95, nr 8, artikkel-id 084039Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We study the role of field redefinitions in general scalar-tensor theories. In particular, we first focus on the class of field redefinitions linear in the spin-2 field and involving derivatives of the spin-0 mode, generically known as disformal transformations. We start by defining the action of a disformal transformation in the tangent space. Then, we take advantage of the great economy of means of the language of differential forms to compute the full transformation of Horndeski's theory under general disformal transformations. We obtain that Horndeski's action maps onto itself modulo a reduced set of non-Horndeski Lagrangians. These new Lagrangians are found to be invariant under disformal transformation that depend only in the first derivatives of the scalar. Moreover, these combinations of Lagrangians precisely appear when expressing in our basis the constraints of the recently proposed extended scalar-tensor theories. These results allow us to classify the different orbits of scalar-tensor theories invariant under particular disformal transformations, namely, the special disformal, kinetic disformal, and disformal Horndeski orbits. In addition, we consider generalizations of this framework. We find that there are possible well-defined extended disformal transformations that have not been considered in the literature. However, they generically cannot link Horndeski theory with extended scalar-tensor theories. Finally, we study further generalizations in which extra fields with different spin are included. These field redefinitions can be used to connect different gravity theories such as multiscalar-tensor theories, generalized Proca theories, and bigravity. We discuss how the formalism of differential forms could be useful for future developments in these lines.

  • 60.
    Millar, Alexander
    et al.
    KTH, Centra, Nordic Institute for Theoretical Physics NORDITA. Stockholm Univ, Dept Phys, Oskar Klein Ctr Cosmoparticle Phys, AlbaNova, S-10691 Stockholm, Sweden.;Stockholm Univ, Roslagstullsbacken 23, S-10691 Stockholm, Sweden..
    Raffelt, Georg
    Werner Heisenberg Inst, Max Planck Inst Phys, Fohringer Ring 6, D-80805 Munich, Germany..
    Stodolsky, Leo
    Werner Heisenberg Inst, Max Planck Inst Phys, Fohringer Ring 6, D-80805 Munich, Germany..
    Vitagliano, Edoardo
    Werner Heisenberg Inst, Max Planck Inst Phys, Fohringer Ring 6, D-80805 Munich, Germany..
    Neutrino mass from bremsstrahlung endpoint in coherent scattering on nuclei2018Inngår i: Physical Review D: covering particles, fields, gravitation, and cosmology, ISSN 2470-0010, E-ISSN 2470-0029, Vol. 98, nr 12, artikkel-id 123006Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We calculate the coherent bremsstrahlung process nu + N -> N + nu + gamma off a nucleus H with the aim of revealing the neutrino mass via the photon endpoint spectrum. Unfortunately, the large required power of a monochromatic neutrino source and/or large detector mass make it difficult to compete with traditional electron-spectrum endpoint measurements in nuclear beta decay. Our neutral-current process distinguishes between Dirac and Majorana neutrinos, but the change of the photon spectrum is of the order of m(nu)/E-nu and thus very small, despite the final-state neutrino coming to rest at the photon endpoint. So the "Dirac-Majorana confusion theorem" remains intact even if E-nu >> m(nu) my applies only for the initial state.

  • 61. Nersisyan, Henrik
    et al.
    Akrami, Yashar
    Amendola, Luca
    Koivisto, Tomi S.
    KTH, Centra, Nordic Institute for Theoretical Physics NORDITA.
    Rubio, Javier
    Solomon, Adam R.
    Instabilities in tensorial nonlocal gravity2017Inngår i: Physical Review D: covering particles, fields, gravitation, and cosmology, ISSN 2470-0010, E-ISSN 2470-0029, Vol. 95, nr 4, artikkel-id 043539Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We discuss the cosmological implications of nonlocal modifications of general relativity containing tensorial structures. Assuming the presence of standard radiation-and matter-dominated eras, we show that, except in very particular cases, the nonlocal terms contribute a rapidly growing energy density. These models therefore generically do not have a stable cosmological evolution.

  • 62.
    Ong, Yen Chin
    et al.
    KTH, Centra, Nordic Institute for Theoretical Physics NORDITA.
    Yao, Yuan
    Yangzhou Univ, Coll Phys Sci & Technol, Ctr Gravitat & Cosmol, Yangzhou 225009, Jiangsu, Peoples R China..
    Generalized uncertainty principle and white dwarfs redux: How the cosmological constant protects the Chandrasekhar limit2018Inngår i: Physical Review D: covering particles, fields, gravitation, and cosmology, ISSN 2470-0010, E-ISSN 2470-0029, Vol. 98, nr 12, artikkel-id 126018Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    It was previously argued that generalized uncertainty principle (GUP) with a positive parameter removes the Chandrasekhar limit. One way to restore the limit is by taking the GUP parameter to be negative. In this work we discuss an alternative method that achieves the same effect: by including a cosmological constant term in the GUP (known as "extended GUP" in the literature). We show that an arbitrarily small but nonzero cosmological constant can restore the Chandrasekhar limit. We also remark that if the extended GUP is correct, then the existence of white dwarfs gives an upper bound for the cosmological constant, which-while still large compared to observation-is approximately 86 orders of magnitude smaller than the natural scale.

  • 63.
    Porter, T. A.
    et al.
    Stanford Univ, WW Hansen Expt Phys Lab, Stanford, CA 94305 USA.;Stanford Univ, Kavli Inst Particle Astrophys & Cosmol, Stanford, CA 94305 USA..
    Rowell, G. P.
    Univ Adelaide, Sch Phys Sci, Adelaide, SA 5000, Australia..
    Johannesson, Guolaugur
    KTH, Centra, Nordic Institute for Theoretical Physics NORDITA. Univ Iceland, Inst Sci, IS-107 Reykjavik, Iceland..
    Moskalenko, I. V.
    Stanford Univ, WW Hansen Expt Phys Lab, Stanford, CA 94305 USA.;Stanford Univ, Kavli Inst Particle Astrophys & Cosmol, Stanford, CA 94305 USA..
    Galactic PeVatrons and helping to find them: Effects of galactic absorption on the observed spectra of very high energy gamma-ray sources2018Inngår i: Physical Review D: covering particles, fields, gravitation, and cosmology, ISSN 2470-0010, E-ISSN 2470-0029, Vol. 98, nr 4, artikkel-id 041302Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Identification of the cosmic-ray (CR) "PeVatrons," which are sources capable of accelerating particles to similar to 10(15) eV energies and higher, may lead to resolving the long-standing question of the origin of the spectral feature in the all-particle CR spectrum known as the "knee." Because CRs with these energies are deflected by interstellar magnetic fields identification of individual sources and determination of their spectral characteristics is more likely via very high energy gamma-ray emissions, which provide the necessary directional information. However, pair production on the interstellar radiation field (ISRF) and cosmic microwave background (CMB) leads to steepening of the high energy tails of gamma-ray spectra, and should be corrected for to enable true properties of the spectrum at the source to be recovered. Employing recently developed three-dimensional ISRF models this paper quantifies the pair-absorption effect on spectra for sources in the Galactic center (GC) direction at 8.5 and 23.5 kpc distances, with the latter corresponding to the far side of the Galactic stellar disc where it is expected that discrimination of spectral features >10 TeV is possible by the forthcoming Cherenkov Telescope Array (CTA). The estimates made suggest spectral cutoffs could be underestimated by factors of a few in the energy range so far sampled by TeV gamma-ray telescopes. As an example to illustrate this, the recent HESS measurements of diffuse gamma-ray emissions possibly associated with injection of CRs nearby Sgr A* are ISRF corrected, and estimates of the spectral cutoff are reevaluated. It is found that it could be higher by up to a factor of similar to 2, indicating that these emissions may be consistent with a CR accelerator with a spectral cutoff of at least 1 PeV at the 95% confidence level.

  • 64. Singh, B.
    et al.
    Erni, W.
    Krusche, B.
    Steinacher, M.
    Walford, N.
    Liu, H.
    Liu, Z.
    Liu, B.
    Shen, X.
    Wang, C.
    Zhao, J.
    Albrecht, M.
    Erlen, T.
    Fink, M.
    Heinsius, F. H.
    Held, T.
    Holtmann, T.
    Jasper, S.
    Keshk, I.
    Koch, H.
    Kopf, B.
    Kuhlmann, M.
    Kuemmel, M.
    Leiber, S.
    Mikirtychyants, M.
    Musiol, P.
    Mustafa, A.
    Pelizaeus, M.
    Pychy, J.
    Richter, M.
    Schnier, C.
    Schroeder, T.
    Sowa, C.
    Steinke, M.
    Triffterer, T.
    Wiedner, U.
    Ball, M.
    Beck, R.
    Hammann, C.
    Ketzer, B.
    Kube, M.
    Mahlberg, P.
    Rossbach, M.
    Schmidt, C.
    Schmitz, R.
    Thoma, U.
    Urban, M.
    Walther, D.
    Wendel, C.
    Wilson, A.
    Bianconi, A.
    Bragadireanu, M.
    Caprini, M.
    Pantea, D.
    Patel, B.
    Czyzycki, W.
    Domagala, M.
    Filo, G.
    Jaworowski, J.
    Krawczyk, M.
    Lisowski, E.
    Lisowski, F.
    Michalek, M.
    Poznanski, P.
    Plazek, J.
    Korcyl, K.
    Kozela, A.
    Kulessa, P.
    Lebiedowicz, P.
    Pysz, K.
    Schaefer, W.
    Szczurek, A.
    Fiutowski, T.
    Idzik, M.
    Mindur, B.
    Przyborowski, D.
    Swientek, K.
    Biernat, J.
    Kamys, B.
    Kistryn, S.
    Korcyl, G.
    Krzemien, W.
    Magiera, A.
    Moskal, P.
    Pyszniak, A.
    Rudy, Z.
    Salabura, P.
    Smyrski, J.
    Strzempek, P.
    Wronska, A.
    Augustin, I.
    Boehm, R.
    Lehmann, I.
    Marinescu, D. Nicmorus
    Schmitt, L.
    Varentsov, V.
    Al-Turany, M.
    Belias, A.
    Deppe, H.
    Veis, N. Divani
    Dzhygadlo, R.
    Ehret, A.
    Flemming, H.
    Gerhardt, A.
    Goetzen, K.
    Gromliuk, A.
    Gruber, L.
    Karabowicz, R.
    Kliemt, R.
    Krebs, M.
    Kurilla, U.
    Lehmann, D.
    Loechner, S.
    Luehning, J.
    Lynen, U.
    Orth, H.
    Patsyuk, M.
    Peters, K.
    Saito, T.
    Schepers, G.
    Schmidt, C. J.
    Schwarz, C.
    Schwiening, J.
    Taeschner, A.
    Traxler, M.
    Ugur, C.
    Voss, B.
    Wieczorek, P.
    Wilms, A.
    Zuehlsdorf, M.
    Abazov, V.
    Alexeev, G.
    Arefiev, V. A.
    Astakhov, V.
    Barabanov, M. Yu.
    Batyunya, B. V.
    Davydov, Y.
    Dodokhov, V. Kh.
    Efremov, A.
    Fechtchenko, A.
    Fedunov, A. G.
    Galoyan, A.
    Grigoryan, S.
    Koshurnikov, E. K.
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    Ohm, H.
    Orfanitski, S.
    Prasuhn, D.
    Prencipe, E.
    Puetz, J.
    Ritman, J.
    Schadmand, S.
    Sefzick, T.
    Serdyuk, V.
    Sterzenbach, G.
    Stockmanns, T.
    Wintz, P.
    Wuestner, P.
    Xu, H.
    Zambanini, A.
    Li, S.
    Li, Z.
    Sun, Z.
    Rigato, V.
    Isaksson, L.
    Achenbach, P.
    Corell, O.
    Denig, A.
    Distler, M.
    Hoek, M.
    Karavdina, A.
    Lauth, W.
    Merkel, H.
    Mueller, U.
    Pochodzalla, J.
    Sanchez, S.
    Schlimme, S.
    Sfienti, C.
    Thiel, M.
    Ahmadi, H.
    Ahmed, S.
    Bleser, S.
    Capozza, L.
    Cardinali, M.
    Dbeyssi, A.
    Deiseroth, M.
    Feldbauer, F.
    Fritsch, M.
    Froerllich, B.
    Kang, D.
    Khaneft, D.
    Klasen, R.
    Leithoff, H. H.
    Lin, D.
    Maas, F.
    Maldaner, S.
    Martinez, M.
    Michel, M.
    Mora Esp, M. C.
    Morales, C. Morales
    Motzko, C.
    Nerling, F.
    Noll, O.
    Pfloeger, S.
    Pitka, A.
    Pineiro, D. Rodriguez
    Sanchez-Lorente, A.
    Steinen, M.
    Valente, R.
    Weber, T.
    Zambrana, M.
    Zimmermann, I.
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    Balanutsa, P.
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    Martin, K.
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    Izotov, A.
    Manaenkov, S.
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    Veretennikov, D.
    Zhdanov, A.
    Bäck, Torbjörn
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Cederwall, Bo
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnfysik.
    Makonyi, K.
    Preston, M.
    Tegner, P. E.
    Woelbing, D.
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    Birsa, R.
    Bradamante, F.
    Bressan, A.
    Martin, A.
    Calen, H.
    Andersson, W. Ikegami
    Johansson, T.
    Kupsc, A.
    Marciniewski, P.
    Papenbrock, M.
    Pettersson, J.
    Schoenning, K.
    Wolke, M.
    Galnander, B.
    Diaz, J.
    Chackara, V. Pothodi
    Chlopik, A.
    Kesik, G.
    Melnychuk, D.
    Slowinski, B.
    Trzcinski, A.
    Wojciechowski, M.
    Wronka, S.
    Zwieglinski, B.
    Buehler, P.
    Marton, J.
    Steinschaden, D.
    Suzuki, K.
    Widmann, E.
    Zmeskal, J.
    Semenov-Tian-Shansky, K. M.
    Feasibility study for the measurement of pi N transition distribution amplitudes at (P)over-barANDA in (P)over-barp -> J/psi pi(0)2017Inngår i: Physical Review D: covering particles, fields, gravitation, and cosmology, ISSN 2470-0010, E-ISSN 2470-0029, Vol. 95, nr 3, artikkel-id 032003Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The exclusive charmonium production process in (P) over barp annihilation with an associated pi 0 meson (p) over barp -> J/psi pi(0) is studied in the framework of QCD collinear factorization. The feasibility of measuring this reaction through the J/psi -> e(+) e(-) decay channel with the AntiProton ANnihilation at DArmstadt ((P) over bar ANDA) experiment is investigated. Simulations on signal reconstruction efficiency as well as the background rejection from various sources including the (P) over barp -> pi(+)pi(-)pi(0) and (p) over barp -> J/psi pi(0)pi(0) reactions are performed with PANDAROOT, the simulation and analysis software framework of the (P) over bar ANDA experiment. It is shown that the measurement can be done at (P) over bar ANDA with significant constraining power under the assumption of an integrated luminosity attainable in four to five months of data taking at the maximum design luminosity.

  • 65.
    Vagnozzi, Sunny
    et al.
    KTH, Centra, Nordic Institute for Theoretical Physics NORDITA. Stockholm Univ, Oskar Klein Ctr Cosmoparticle Phys, Dept Phys, Alballova Univ Ctr, Roslagstullsbacken 21A, SE-10691 Stockholm, SwedenStockholm Univ, Roslagstullsbacken 23, S-10691 Stockholm, Sweden.;Univ Cambridge, Kavh Inst Cosmol KICC, Madingley Rd, Cambridge CB3 0HA, England.;Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Visinelli, Luca
    Stockholm Univ, Roslagstullsbacken 23, S-10691 Stockholm, Sweden.;Uppsala Univ, Dept Phys & Astron, Lagerhyddsvagen 1, S-75120 Uppsala, Sweden.;Univ Amsterdam, Gravitat Astroparticle Phys Amsterdam GRAPPA, Inst Theoret Phys Amsterdam, Sci Pk 904, NL-1098 XH Amsterdam, Netherlands.;Univ Amsterdam, Delta Inst Theoret Phys, Sci Pk 904, NL-1098 XH Amsterdam, Netherlands..
    Hunting for extra dimensions in the shadow of M872019Inngår i: Physical Review D: covering particles, fields, gravitation, and cosmology, ISSN 2470-0010, E-ISSN 2470-0029, Vol. 100, nr 2, artikkel-id 024020Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Event Horizon Telescope has recently provided the first image of the dark shadow around the supermassive black hole M87*. The observation of a highly circular shadow provides strong limits on deviations of M87*'s quadrupole moment from the Kerr value. We show that the absence of such a deviation can be used to constrain the physics of extra dimensions of spacetime. Focusing on the Randall-Sundrum AdS(5) brane-world scenario, we show that the observation of M87*'s dark shadow sets the limit l less than or similar to 170 AU, where l is the AdS(5) curvature radius. This limit is among the first quantitative constraints on exotic physics obtained from the extraordinary first ever image of the dark shadow of a black hole.

  • 66.
    Visinelli, Luca
    KTH, Centra, Nordic Institute for Theoretical Physics NORDITA.
    Light axion-like dark matter must be present during inflation2017Inngår i: Physical Review D: covering particles, fields, gravitation, and cosmology, ISSN 2470-0010, E-ISSN 2470-0029, Vol. 96, nr 2, artikkel-id 023013Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Axion-like particles (ALPs) might constitute the totality of the cold dark matter (CDM) observed. The parameter space of ALPs depends on the mass of the particle m and on the energy scale of inflation HI, the latter being bound by the nondetection of primordial gravitational waves. We show that the bound on HI implies the existence of a mass scale mχ=10 neV-0.5 peV, depending on the ALP susceptibility χ, such that the energy density of ALPs of mass smaller than mχ is too low to explain the present CDM budget, if the ALP field has originated after the end of inflation. This bound affects ultra-light axions (ULAs), which have recently regained popularity as CDM candidates. Light (m<mχ) ALPs can then be CDM candidates only if the ALP field has already originated during the inflationary period, in which case the parameter space is constrained by the nondetection of axion isocurvature fluctuations. We comment on the effects on these bounds from additional physics beyond the standard model, besides ALPs.

  • 67.
    Visinelli, Luca
    et al.
    KTH, Centra, Nordic Institute for Theoretical Physics NORDITA.
    Bolis, Nadia
    Fyzikalni Ustav Akad CR, Cent European Inst Cosmol & Fundamental Phys CEIC, Na Slovance 1999-2, CZ-18221 Prague 8, Czech Republic..
    Vagnozzi, Sunny
    Stockholm Univ, Dept Phys, Oskar Klein Ctr Cosmoparticle Phys, AlbaNova Univ Ctr, Roslagstullbacken 21A, SE-10691 Stockholm, Sweden..
    Brane-world extra dimensions in light of GW1708172018Inngår i: Physical Review D: covering particles, fields, gravitation, and cosmology, ISSN 2470-0010, E-ISSN 2470-0029, Vol. 97, nr 6, artikkel-id 064039Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The search for extra dimensions is a challenging endeavor to probe physics beyond the Standard Model. The joint detection of gravitational waves (GW) and electromagnetic (EM) signals from the merging of a binary system of compact objects like neutron stars can help constrain the geometry of extra dimensions beyond our 3 + 1 spacetime ones. A theoretically well-motivated possibility is that our observable Universe is a 3 + 1-dimensional hypersurface, or brane, embedded in a higher 4 + 1-dimensional antide Sitter (AdS(5)) spacetime, in which gravity is the only force which propagates through the infinite bulk space, while other forces are confined to the brane. In these types of brane-world models, GW and EM signals between two points on the brane would, in general, travel different paths. This would result in a time lag between the detection of GW and EM signals emitted simultaneously from the same source. We consider the recent near-simultaneous detection of the GW event GW170817 from the LIGO/Virgo collaboration, and its EM counterpart, the short gamma-ray burst GRB170817A detected by the Fermi Gamma-ray Burst Monitor and the International Gamma-Ray Astrophysics Laboratory Anti-Coincidence Shield spectrometer. Assuming the standard.-cold dark matter scenario and performing a likelihood analysis which takes into account astrophysical uncertainties associated to the measured time lag, we set an upper limit of l less than or similar to 0.535 Mpc at 68% confidence level on the AdS(5) radius of curvature l. Although the bound is not competitive with current Solar System constraints, it is the first time that data from a multimessenger GW-EM measurement is used to constrain extra-dimensional models. Thus, our work provides a proof of principle for the possibility of using multimessenger astronomy for probing the geometry of our space-time.

  • 68.
    Visinelli, Luca
    et al.
    Stockholm Univ, Oskar Klein Ctr Cosmoparticle Phys, Roslagstullsbacken 21A, SE-10691 Stockholm, Sweden..;Uppsala Univ, Dept Phys & Astron, Lagerhyddsvagen 1, S-75120 Uppsala, Sweden..
    Vagnozzi, Sunny
    KTH, Centra, Nordic Institute for Theoretical Physics NORDITA. Stockholm Univ, Oskar Klein Ctr Cosmoparticle Phys, Roslagstullsbacken 21A, SE-10691 Stockholm, Sweden.
    Cosmological window onto the string axiverse and the supersymmetry breaking scale2019Inngår i: Physical Review D: covering particles, fields, gravitation, and cosmology, ISSN 2470-0010, E-ISSN 2470-0029, Vol. 99, nr 6, artikkel-id 063517Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In the simplest picture, the masses of string axions populating the axiverse depend on two parameters: the supersymmetry-breaking scale M-susy and the action S of the string instantons responsible for breaking the axion shift symmetry. In this work, we explore whether cosmological data can be used to probe these two parameters. Adopting string-inspired flat priors on log(10) M-susy and S and imposing that M-susy be sub-Planckian, we find S = 198 +/- 28. These bounds suggest that cosmological data complemented with string-inspired priors select a quite narrow axion mass range within the axiverse, log(10)(m(a)/eV) = -21.5(-2.3)(+1.3). We find that M-susy remains unconstrained due to a fundamental parameter degeneracy with S. We explore the significant impact of other choices of priors on the results, and we comment on similar findings in recent previous literature.

  • 69.
    Winkler, Martin Wolfgang
    KTH, Centra, Nordic Institute for Theoretical Physics NORDITA.
    Decay and detection of a light scalar boson mixing with the Higgs boson2019Inngår i: Physical Review D: covering particles, fields, gravitation, and cosmology, ISSN 2470-0010, E-ISSN 2470-0029, Vol. 99, nr 1, artikkel-id 015018Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The simplest extension of the standard model consists in adding one singlet scalar field which mixes with the Higgs boson. O(GeV) masses of the new scalar carry strong motivation from relaxion, dark matter and inflation models. The decay of a GeV scalar is, however, notoriously difficult to address since, at this mass scale, the chiral expansion breaks down and perturbative QCD does not apply. Existing estimates of the GeV scalar decay rate disagree by several orders of magnitude. In this work, we perform a new dispersive analysis in order to strongly reduce these uncertainties and to address discrepancies in earlier results. We will update existing limits on light scalars and future experimental sensitivities which are in some cases strongly affected by the new-found decay rates. The meson form factors provided in this work, can be used to generalize our findings to non-universally coupled light scalars.

12 51 - 69 of 69
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