High Energy Astrophysical Phenomena Publications (50)

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High Energy Astrophysical Phenomena Publications

We consider the electromagnetic radiation from newborn binary black holes (BBHs) formed by the evolution of isolated massive stellar binaries. Before the formation of a BBH, the binary consists of a primary black hole (BH) and a secondary Wolf-Rayet star. We investigate two types of transients from the birth of a secondary BH: one powered by the Bondi-Hoyle-Lyttleton accretion onto the primary BH, and the other induced by accretion onto the secondary BH. Read More


An energy extracting black hole magnetosphere can be defined by the location of its inner Alfv\'{e}n surface, which determines the rate of black hole energy extraction along a given magnetic field line. We study how the location of the inner Alfv\'{e}n surface can modify the structure of energy extracting black hole magnetospheres in the force-free limit. Hundreds of magnetospheres are numerically computed via a general relativistic extension of the Newtonian magnetofrictional method for a full range of black hole spins and flow parameters. Read More


The equilibrium-diffusion approximation (EDA) is used to describe certain radiation-hydrodynamic (RH) environments. When this is done the RH equations reduce to a simplified set of equations. The EDA can be derived by asymptotically analyzing the full set of RH equations in the equilibrium-diffusion limit. Read More


Here we present the evidence for periodicity of an optical emission detected in several AGN. Significant periodicity is found in light curves and radial velocity curves. We discuss possible mechanisms that could produce such periodic variability and their implications. Read More


2017Feb
Affiliations: 1Univ. Paris-Sud, Orsay, 2ICRR, University of Tokyo, 3Universite Libre de Bruxelles

Ultra-high energy cosmic rays (UHECRs) are particles, likely protons and/or nuclei, with energies up to $10^{20}$ eV that are observed through the giant air showers they produce in the atmosphere. These particles carry the information on the most extreme phenomena in the Universe. At these energies, even charged particles could be magnetically rigid enough to keep track of, or even point directly to, the original positions of their sources on the sky. Read More


We propose to use degree-scale angular clustering of fast radio bursts (FRBs) to identify their origin and the host galaxy population. We study the information content in auto-correlation of the angular positions and dispersion measures (DM) and in cross-correlation with galaxies. We show that the cross-correlation with Sloan Digital Sky Survey (SDSS) galaxies will place stringent constraints on the mean physical quantities associated with FRBs. Read More


The third Fermi Large Area Telescope (LAT) $\gamma$-ray source catalog (3FGL) contains over 1000 objects for which there is no known counterpart at other wavelengths. The physical origin of the $\gamma$-ray emission of those objects is unknown. Such objects are commonly referred to as unassociated and mostly do not exhibit significant $\gamma$-ray flux variability. Read More


The discovery of gravitational waves by the international collaboration LIGO (Laser Interferometer Gravitational-Wave Observatory)/Virgo on the one hand is a triumphant confirmation of the general theory of relativity, and on the other confirms the general fundamental ideas on the nuclear evolution of baryon matter in the Universe concentrated in binary stars. LIGO/Virgo may turn out to be the first experiment in the history of physics to detect two physical entities, gravitational waves and black holes Read More


Ten weeks' daily imaging of the giant elliptical galaxy M87 with the Hubble Space Telescope has yielded 41 nova light curves of unprecedented quality for extragalactic cataclysmic variables. We have recently used these light curves to demonstrate that the observational scatter in the so-called Maximum-Magnitude Rate of Decline (MMRD) relation for classical novae is so large as to render the nova-MMRD useless as a standard candle. Here we demonstrate that the Buscombe - de Vaucouleurs hypothesis, that all novae converge to nearly the same absolute magnitude about two weeks after maximum light, is strongly supported by our M87 nova data. Read More


Ultra-high-energy cosmic rays (UHECRs) can be accelerated by tidal disruption events of stars by black holes. Encounters between white dwarfs with intermediate-mass black holes (IMBHs) provide a natural environment for acceleration, as tidal forces can ignite nuclear burn and lead to a supernova explosion. The numbers of IMBHs may be substantially augmented once account is taken of their likely presence in dwarf galaxies. Read More


2017Feb
Affiliations: 1University of New Hampshire, 2IRAP, France, 3Peking University, China, 4IRAP, France, 5IRAP, France, 6University of Alabama

The X-ray source 2XMM J123103.2+110648 was previously found to show pure thermal X-ray spectra and a ~3.8 hr periodicity in three XMM-Newton X-ray observations in 2003-2005, and the optical spectrum of the host galaxy suggested it as a type 2 active galactic nucleus candidate. Read More


The explosion mechanism of core-collapse supernovae is a long-standing problem in stellar astrophysics. We briefly outline the main contenders for a solution and review recent efforts to model core-collapse supernova explosions by means of multi-dimensional simulations. We discuss several suggestions for solving the problem of missing or delayed neutrino-driven explosions in three-dimensional supernova models, including -- among others -- variations in the microphysics and large seed perturbations in convective burning shells. Read More


We present a thermodynamically consistent method by which equations of state based on nonrelativistic potential models can be modified so that they respect causality at high densities, both at zero and finite temperature (entropy). We illustrate the application of the method using the high density phase parametrization of the well known APR model in its pure neutron matter configuration as an example. We also show that, for models with only contact interactions, the adiabatic speed of sound is independent of the temperature in the limit of very large temperature. Read More


During the accretion phase of a core-collapse supernovae, large amplitude turbulence is generated by the combination of the standing accretion shock instability and convection driven by neutrino heating. The turbulence directly affects the dynamics of the explosion, but there is also the possibility of an additional, indirect, feedback mechanism due to the effect turbulence can have upon neutrino flavor evolution and thus the neutrino heating. In this paper we consider the effect of turbulence during the accretion phase upon neutrino evolution, both numerically and analytically. Read More


2017Feb
Authors: M. G. Aartsen, M. Ackermann, J. Adams, J. A. Aguilar, M. Ahlers, M. Ahrens, I. Al Samarai, D. Altmann, K. Andeen, T. Anderson, I. Ansseau, G. Anton, M. Archinger, C. Argüelles, J. Auffenberg, S. Axani, H. Bagherpour, X. Bai, S. W. Barwick, V. Baum, R. Bay, J. J. Beatty, J. Becker Tjus, K. -H. Becker, S. BenZvi, D. Berley, E. Bernardini, D. Z. Besson, G. Binder, D. Bindig, E. Blaufuss, S. Blot, C. Bohm, M. Börner, F. Bos, D. Bose, S. Böser, O. Botner, J. Braun, L. Brayeur, H. -P. Bretz, S. Bron, A. Burgman, T. Carver, M. Casier, E. Cheung, D. Chirkin, A. Christov, K. Clark, L. Classen, S. Coenders, G. H. Collin, J. M. Conrad, D. F. Cowen, R. Cross, M. Day, J. P. A. M. de André, C. De Clercq, E. del Pino Rosendo, H. Dembinski, S. De Ridder, P. Desiati, K. D. de Vries, G. de Wasseige, M. de With, T. DeYoung, J. C. Díaz-Vélez, V. di Lorenzo, H. Dujmovic, J. P. Dumm, M. Dunkman, B. Eberhardt, T. Ehrhardt, B. Eichmann, P. Eller, S. Euler, P. A. Evenson, S. Fahey, A. R. Fazely, J. Feintzeig, J. Felde, K. Filimonov, C. Finley, S. Flis, C. -C. Fösig, A. Franckowiak, E. Friedman, T. Fuchs, T. K. Gaisser, J. Gallagher, L. Gerhardt, K. Ghorbani, W. Giang, L. Gladstone, T. Glauch, T. Glüsenkamp, A. Goldschmidt, J. G. Gonzalez, D. Grant, Z. Griffith, C. Haack, A. Hallgren, F. Halzen, E. Hansen, T. Hansmann, K. Hanson, D. Hebecker, D. Heereman, K. Helbing, R. Hellauer, S. Hickford, J. Hignight, G. C. Hill, K. D. Hoffman, R. Hoffmann, K. Hoshina, F. Huang, M. Huber, K. Hultqvist, S. In, A. Ishihara, E. Jacobi, G. S. Japaridze, M. Jeong, K. Jero, B. J. P. Jones, W. Kang, A. Kappes, T. Karg, A. Karle, U. Katz, M. Kauer, A. Keivani, J. L. Kelley, A. Kheirandish, J. Kim, M. Kim, T. Kintscher, J. Kiryluk, T. Kittler, S. R. Klein, G. Kohnen, R. Koirala, H. Kolanoski, R. Konietz, L. Köpke, C. Kopper, S. Kopper, D. J. Koskinen, M. Kowalski, K. Krings, M. Kroll, G. Krückl, C. Krüger, J. Kunnen, S. Kunwar, N. Kurahashi, T. Kuwabara, A. Kyriacou, M. Labare, J. L. Lanfranchi, M. J. Larson, F. Lauber, D. Lennarz, M. Lesiak-Bzdak, M. Leuermann, L. Lu, J. Lünemann, J. Madsen, G. Maggi, K. B. M. Mahn, S. Mancina, M. Mandelartz, R. Maruyama, K. Mase, R. Maunu, F. McNally, K. Meagher, M. Medici, M. Meier, T. Menne, G. Merino, T. Meures, S. Miarecki, J. Micallef, G. Momenté, T. Montaruli, M. Moulai, R. Nahnhauer, U. Naumann, G. Neer, H. Niederhausen, S. C. Nowicki, D. R. Nygren, A. Obertacke Pollmann, A. Olivas, A. O'Murchadha, T. Palczewski, H. Pandya, D. V. Pankova, P. Peiffer, Ö. Penek, J. A. Pepper, C. Pérez de los Heros, D. Pieloth, E. Pinat, P. B. Price, G. T. Przybylski, M. Quinnan, C. Raab, L. Rädel, M. Rameez, K. Rawlins, R. Reimann, B. Relethford, M. Relich, E. Resconi, W. Rhode, M. Richman, B. Riedel, S. Robertson, M. Rongen, C. Rott, T. Ruhe, D. Ryckbosch, D. Rysewyk, L. Sabbatini, S. E. Sanchez Herrera, A. Sandrock, J. Sandroos, S. Sarkar, K. Satalecka, P. Schlunder, T. Schmidt, S. Schoenen, S. Schöneberg, L. Schumacher, D. Seckel, S. Seunarine, D. Soldin, M. Song, G. M. Spiczak, C. Spiering, J. Stachurska, T. Stanev, A. Stasik, J. Stettner, A. Steuer, T. Stezelberger, R. G. Stokstad, A. Stößl, R. Ström, N. L. Strotjohann, G. W. Sullivan, M. Sutherland, H. Taavola, I. Taboada, J. Tatar, F. Tenholt, S. Ter-Antonyan, A. Terliuk, G. Tešić, S. Tilav, P. A. Toale, M. N. Tobin, S. Toscano, D. Tosi, M. Tselengidou, C. F. Tung, A. Turcati, E. Unger, M. Usner, J. Vandenbroucke, N. van Eijndhoven, S. Vanheule, M. van Rossem, J. van Santen, M. Vehring, M. Voge, E. Vogel, M. Vraeghe, C. Walck, A. Wallace, M. Wallraff, N. Wandkowsky, A. Waza, Ch. Weaver, M. J. Weiss, C. Wendt, S. Westerhoff, B. J. Whelan, S. Wickmann, K. Wiebe, C. H. Wiebusch, L. Wille, D. R. Williams, L. Wills, M. Wolf, T. R. Wood, E. Woolsey, K. Woschnagg, D. L. Xu, X. W. Xu, Y. Xu, J. P. Yanez, G. Yodh, S. Yoshida, M. Zoll

We present an all-sky search for muon neutrinos produced during the prompt $\gamma$-ray emission of 1172 gamma-ray bursts (GRBs) with the IceCube Neutrino Observatory. The detection of these neutrinos would constitute evidence for ultra-high energy cosmic ray (UHECR) production in GRBs, as interactions between accelerated protons and the prompt $\gamma$-ray field would yield charged pions, which decay to neutrinos. A previously reported search for muon neutrino tracks from Northern Hemisphere GRBs has been extended to include three additional years of IceCube data. Read More


Neutrino flux streaming from a supernova can undergo rapid flavor conversions almost immediately above the core. Focusing on this region, we study these fast conversions using a linear stability analysis. We find that, for realistic angular distributions of neutrinos, fast conversions can occur within a few nanoseconds in regions just above the neutrinosphere. Read More


2017Feb
Affiliations: 1University of Leicester, 2University of Leicester, 3University of Leicester, 4CSIC-Universidad de Cantabria, 5ESAC, 6University of Leicester, 7University of Leicester

We present optical spectroscopy of candidate AGN pinpointed by a Swift follow-up campaign on unidentified transients in the XMM-Newton Slew Survey, increasing the completeness of the identifications of AGN in the Survey. Our Swift follow-up campaign identified 17 XRT-detected candidate AGN, of which nine were selected for optical follow-up and a further two were confirmed as AGN elsewhere. Using data obtained at the William Herschel Telescope, Very Large Telescope and New Technology Telescope, we find AGN features in seven of the candidates. Read More


2017Feb
Authors: MAGIC Collaboration, M. L. Ahnen1, S. Ansoldi2, L. A. Antonelli3, P. Antoranz4, C. Arcaro5, A. Babic6, B. Banerjee7, P. Bangale8, U. Barres de Almeida9, J. A. Barrio10, W. Bednarek11, E. Bernardini12, A. Berti13, B. Biasuzzi14, A. Biland15, O. Blanch16, S. Bonnefoy17, G. Bonnoli18, F. Borracci19, T. Bretz20, S. Buson21, A. Carosi22, A. Chatterjee23, R. Clavero24, P. Colin25, E. Colombo26, J. L. Contreras27, J. Cortina28, S. Covino29, P. Da Vela30, F. Dazzi31, A. De Angelis32, B. De Lotto33, E. de Oña Wilhelmi34, F. Di Pierro35, M. Doert36, A. Domínguez37, D. Dominis Prester38, D. Dorner39, M. Doro40, S. Einecke41, D. Eisenacher Glawion42, D. Elsaesser43, M. Engelkemeier44, V. Fallah Ramazani45, A. Fernández-Barral46, D. Fidalgo47, M. V. Fonseca48, L. Font49, K. Frantzen50, C. Fruck51, D. Galindo52, R. J. García López53, M. Garczarczyk54, D. Garrido Terrats55, M. Gaug56, P. Giammaria57, N. Godinović58, D. Gora59, D. Guberman60, D. Hadasch61, A. Hahn62, M. Hayashida63, J. Herrera64, J. Hose65, D. Hrupec66, G. Hughes67, W. Idec68, K. Kodani69, Y. Konno70, H. Kubo71, J. Kushida72, A. La Barbera73, D. Lelas74, E. Lindfors75, S. Lombardi76, F. Longo77, M. López78, R. López-Coto79, P. Majumdar80, M. Makariev81, K. Mallot82, G. Maneva83, M. Manganaro84, N. Mankuzhiyil85, K. Mannheim86, L. Maraschi87, B. Marcote88, M. Mariotti89, M. Martínez90, D. Mazin91, U. Menzel92, J. M. Miranda93, R. Mirzoyan94, A. Moralejo95, E. Moretti96, D. Nakajima97, V. Neustroev98, A. Niedzwiecki99, M. Nievas Rosillo100, K. Nilsson101, K. Nishijima102, K. Noda103, L. Nogués104, S. Paiano105, J. Palacio106, M. Palatiello107, D. Paneque108, R. Paoletti109, J. M. Paredes110, X. Paredes-Fortuny111, G. Pedaletti112, M. Peresano113, L. Perri114, M. Persic115, J. Poutanen116, P. G. Prada Moroni117, E. Prandini118, I. Puljak119, J. R. Garcia120, I. Reichardt121, W. Rhode122, M. Ribó123, J. Rico124, T. Saito125, K. Satalecka126, S. Schroeder127, T. Schweizer128, S. N. Shore129, A. Sillanpää130, J. Sitarek131, I. Snidaric132, D. Sobczynska133, A. Stamerra134, M. Strzys135, T. Surić136, L. Takalo137, H. Takami138, F. Tavecchio139, P. Temnikov140, T. Terzić141, D. Tescaro142, M. Teshima143, D. F. Torres144, T. Toyama145, A. Treves146, G. Vanzo147, V. Verguilov148, I. Vovk149, J. E. Ward150, M. Will151, M. H. Wu152, R. Zanin153, Fermi-LAT collaboration154, :155, J. Becerra González156, B. Rani157, F. Krauss158, M. Perri159, F. Verrecchia160, R. Reinthal161
Affiliations: 1ETH Zurich, 2Università di Udine, INFN Trieste, 3INAF National Institute for Astrophysics, 4Università di Siena, INFN Pisa, 5Università di Padova and INFN, 6Croatian MAGIC Consortium, Rudjer Boskovic Institute, University of Rijeka, University of Split and University of Zagreb, Croatia, 7Saha Institute of Nuclear Physics, 1/AF Bidhannagar, 8Max-Planck-Institut für Physik, 9Max-Planck-Institut für Physik, 10Universidad Complutense, 11University of Łódź, 12Deutsches Elektronen-Synchrotron, 13Università di Udine, INFN Trieste, 14Università di Udine, INFN Trieste, 15ETH Zurich, 16Institut de Fisica d'Altes Energies, 17Universidad Complutense, 18Università di Siena, INFN Pisa, 19Max-Planck-Institut für Physik, 20Universität Würzburg, 21Università di Padova and INFN, 22INAF National Institute for Astrophysics, 23Saha Institute of Nuclear Physics, 1/AF Bidhannagar, 24Inst. de Astrofísica de Canarias, Universidad de La Laguna, Dpto. Astrofísica, 25Max-Planck-Institut für Physik, 26Inst. de Astrofísica de Canarias, Universidad de La Laguna, Dpto. Astrofísica, 27Universidad Complutense, 28Institut de Fisica d'Altes Energies, 29INAF National Institute for Astrophysics, 30Università di Siena, INFN Pisa, 31Max-Planck-Institut für Physik, 32Università di Padova and INFN, 33Università di Udine, INFN Trieste, 34Institute for Space Sciences, 35INAF National Institute for Astrophysics, 36Technische Universität Dortmund, 37Universidad Complutense, 38Croatian MAGIC Consortium, Rudjer Boskovic Institute, University of Rijeka, University of Split and University of Zagreb, Croatia, 39Universität Würzburg, 40Università di Padova and INFN, 41Technische Universität Dortmund, 42Universität Würzburg, 43Technische Universität Dortmund, 44Technische Universität Dortmund, 45Finnish MAGIC Consortium, Tuorla Observatory, University of Turku and Astronomy Division, University of Oulu, Finland, 46Institut de Fisica d'Altes Energies, 47Universidad Complutense, 48Universidad Complutense, 49Unitat de Física de les Radiacions, Departament de Física, and CERES-IEEC, Universitat Autònoma de Barcelona, 50Technische Universität Dortmund, 51Max-Planck-Institut für Physik, 52Universitat de Barcelona, ICC, 53Inst. de Astrofísica de Canarias, Universidad de La Laguna, Dpto. Astrofísica, 54Deutsches Elektronen-Synchrotron, 55Unitat de Física de les Radiacions, Departament de Física, and CERES-IEEC, Universitat Autònoma de Barcelona, 56Unitat de Física de les Radiacions, Departament de Física, and CERES-IEEC, Universitat Autònoma de Barcelona, 57INAF National Institute for Astrophysics, 58Croatian MAGIC Consortium, Rudjer Boskovic Institute, University of Rijeka, University of Split and University of Zagreb, Croatia, 59Deutsches Elektronen-Synchrotron, 60Institut de Fisica d'Altes Energies, 61Japanese MAGIC Consortium, ICRR, The University of Tokyo, Department of Physics and Hakubi Center, Kyoto University, Tokai University, The University of Tokushima, 62Max-Planck-Institut für Physik, 63Japanese MAGIC Consortium, ICRR, The University of Tokyo, Department of Physics and Hakubi Center, Kyoto University, Tokai University, The University of Tokushima, 64Inst. de Astrofísica de Canarias, Universidad de La Laguna, Dpto. Astrofísica, 65Max-Planck-Institut für Physik, 66Croatian MAGIC Consortium, Rudjer Boskovic Institute, University of Rijeka, University of Split and University of Zagreb, Croatia, 67ETH Zurich, 68University of Łódź, 69Japanese MAGIC Consortium, ICRR, The University of Tokyo, Department of Physics and Hakubi Center, Kyoto University, Tokai University, The University of Tokushima, 70Japanese MAGIC Consortium, ICRR, The University of Tokyo, Department of Physics and Hakubi Center, Kyoto University, Tokai University, The University of Tokushima, 71Japanese MAGIC Consortium, ICRR, The University of Tokyo, Department of Physics and Hakubi Center, Kyoto University, Tokai University, The University of Tokushima, 72Japanese MAGIC Consortium, ICRR, The University of Tokyo, Department of Physics and Hakubi Center, Kyoto University, Tokai University, The University of Tokushima, 73INAF National Institute for Astrophysics, 74Croatian MAGIC Consortium, Rudjer Boskovic Institute, University of Rijeka, University of Split and University of Zagreb, Croatia, 75Finnish MAGIC Consortium, Tuorla Observatory, University of Turku and Astronomy Division, University of Oulu, Finland, 76INAF National Institute for Astrophysics, 77Università di Udine, INFN Trieste, 78Universidad Complutense, 79Institut de Fisica d'Altes Energies, 80Saha Institute of Nuclear Physics, 1/AF Bidhannagar, 81Inst. for Nucl. Research and Nucl. Energy, 82Deutsches Elektronen-Synchrotron, 83Inst. for Nucl. Research and Nucl. Energy, 84Inst. de Astrofísica de Canarias, Universidad de La Laguna, Dpto. Astrofísica, 85Università di Udine, INFN Trieste, 86Universität Würzburg, 87INAF National Institute for Astrophysics, 88Universitat de Barcelona, ICC, 89Università di Padova and INFN, 90Institut de Fisica d'Altes Energies, 91Max-Planck-Institut für Physik, 92Max-Planck-Institut für Physik, 93Università di Siena, INFN Pisa, 94Max-Planck-Institut für Physik, 95Institut de Fisica d'Altes Energies, 96Max-Planck-Institut für Physik, 97Japanese MAGIC Consortium, ICRR, The University of Tokyo, Department of Physics and Hakubi Center, Kyoto University, Tokai University, The University of Tokushima, 98Finnish MAGIC Consortium, Tuorla Observatory, University of Turku and Astronomy Division, University of Oulu, Finland, 99University of Łódź, 100Universidad Complutense, 101Finnish MAGIC Consortium, Tuorla Observatory, University of Turku and Astronomy Division, University of Oulu, Finland, 102Japanese MAGIC Consortium, ICRR, The University of Tokyo, Department of Physics and Hakubi Center, Kyoto University, Tokai University, The University of Tokushima, 103Max-Planck-Institut für Physik, 104Institut de Fisica d'Altes Energies, 105Università di Padova and INFN, 106Institut de Fisica d'Altes Energies, 107Università di Udine, INFN Trieste, 108Max-Planck-Institut für Physik, 109Università di Siena, INFN Pisa, 110Universitat de Barcelona, ICC, 111Universitat de Barcelona, ICC, 112Deutsches Elektronen-Synchrotron, 113Università di Udine, INFN Trieste, 114INAF National Institute for Astrophysics, 115Università di Udine, INFN Trieste, 116Finnish MAGIC Consortium, Tuorla Observatory, University of Turku and Astronomy Division, University of Oulu, Finland, 117Università di Pisa, and INFN Pisa, 118ETH Zurich, 119Croatian MAGIC Consortium, Rudjer Boskovic Institute, University of Rijeka, University of Split and University of Zagreb, Croatia, 120Max-Planck-Institut für Physik, 121Università di Padova and INFN, 122Technische Universität Dortmund, 123Universitat de Barcelona, ICC, 124Institut de Fisica d'Altes Energies, 125Japanese MAGIC Consortium, ICRR, The University of Tokyo, Department of Physics and Hakubi Center, Kyoto University, Tokai University, The University of Tokushima, 126Deutsches Elektronen-Synchrotron, 127Technische Universität Dortmund, 128Max-Planck-Institut für Physik, 129Università di Pisa, and INFN Pisa, 130Finnish MAGIC Consortium, Tuorla Observatory, University of Turku and Astronomy Division, University of Oulu, Finland, 131University of Łódź, 132Croatian MAGIC Consortium, Rudjer Boskovic Institute, University of Rijeka, University of Split and University of Zagreb, Croatia, 133University of Łódź, 134INAF National Institute for Astrophysics, 135Max-Planck-Institut für Physik, 136Croatian MAGIC Consortium, Rudjer Boskovic Institute, University of Rijeka, University of Split and University of Zagreb, Croatia, 137Finnish MAGIC Consortium, Tuorla Observatory, University of Turku and Astronomy Division, University of Oulu, Finland, 138Japanese MAGIC Consortium, ICRR, The University of Tokyo, Department of Physics and Hakubi Center, Kyoto University, Tokai University, The University of Tokushima, 139INAF National Institute for Astrophysics, 140Inst. for Nucl. Research and Nucl. Energy, 141Croatian MAGIC Consortium, Rudjer Boskovic Institute, University of Rijeka, University of Split and University of Zagreb, Croatia, 142Università di Padova and INFN, 143Max-Planck-Institut für Physik, 144ICREA and Institute for Space Sciences, 145Max-Planck-Institut für Physik, 146Università di Udine, INFN Trieste, 147Inst. de Astrofísica de Canarias, Universidad de La Laguna, Dpto. Astrofísica, 148Inst. for Nucl. Research and Nucl. Energy, 149Max-Planck-Institut für Physik, 150Institut de Fisica d'Altes Energies, 151Inst. de Astrofísica de Canarias, Universidad de La Laguna, Dpto. Astrofísica, 152Institute for Space Sciences, 153Universitat de Barcelona, ICC, 154Inst. de Astrofísica de Canarias, Universidad de La Laguna, Dpto. Astrofísica, 155Inst. de Astrofísica de Canarias, Universidad de La Laguna, Dpto. Astrofísica, 156Inst. de Astrofísica de Canarias, Universidad de La Laguna, Dpto. Astrofísica, 157NASA Goddard Space Flight Center, 158GRAPPA and Anton Pannekoek Institute for Astronomy, University of Amsterdam, 159INAF National Institute for Astrophysics, 160INAF National Institute for Astrophysics, 161Finnish MAGIC Consortium, Tuorla Observatory, University of Turku and Astronomy Division, University of Oulu, Finland

We present the first detection of the nearby (z=0.084) low-luminosity BL Lac object 1ES 1741+196 in the very high energy (VHE: E$>$100 GeV) band. This object lies in a triplet of interacting galaxies. Read More


Relativistic jets of plasma are a key ingredient of many types of Active Galactic Nuclei (AGN). Today we know that AGNs are powered by the accretion of inter stellar material into the gravitational field of a Super Massive Black Hole and that this process can release as much power as a whole galaxy, like the Milky Way, from a region that is comparable to the Solar System in size. Depending on the properties of the central energy source, a large fraction of this power can be involved in the acceleration of magnetized plasmas at relativistic speeds, to form large scale jets. Read More


Strong winds from massive stars are a topic of interest to a wide range of astrophysical fields. In High-Mass X-ray Binaries the presence of an accreting compact object on the one side allows to infer wind parameters from studies of the varying properties of the emitted X-rays; but on the other side the accretor's gravity and ionizing radiation can strongly influence the wind flow. Based on a collaborative effort of astronomers both from the stellar wind and the X-ray community, this presentation attempts to review our current state of knowledge and indicate avenues for future progress. Read More


When supernovae enter the nebular phase after a few months, they reveal spectral fingerprints of their deep interiors, glowing by radioactivity produced in the explosion. We are given a unique opportunity to see what an exploded star looks like inside. The line profiles and luminosities encode information about physical conditions, explosive and hydrostatic nucleosynthesis, and ejecta morphology, which link to the progenitor properties and the explosion mechanism. Read More


We estimate the mass of the compact object in the gamma-ray binaries LSI+61303 and MWC 148, using the latest data for the inclination, orbital motion and assuming that the orbital plane coincides with the equatorial plane of the Be star. For LSI+61303 we find the mass of the compact object to be most likely in the range 1.3 M_sun < M_2 < 2. Read More


During our optical monitoring of UV Ceti, iconic late-type flaring star, with high temporal resolution using the Russian 6-m telescope in 2008 we detected a giant flare with the amplitude of about 3 magnitudes in $U$-band. Near flare maximum more than a dozen of spike bursts have been discovered with triangular shapes and durations from 0.6 to 1. Read More


The formation of relativistic jets in active galactic nuclei (AGN) is related to accretion on to their central supermassive black holes, and magnetic fields are believed to play a central role in launching, collimating and accelerating the jet streams from very compact regions out to kiloparsec or megaparsec scales. In the presence of helical or toroidal magnetic fields threading the AGN jets and their immediate vicinity, gradients in the observed Faraday rotation measures are expected due to the systematic change in the line-of-sight component of the magnetic field across the jet. We have analysed total intensity, linear polarization, fractional polarization and Faraday rotation maps based on Very Long Baseline Array data obtained at four wavelengths in the 18-22 cm range for six AGN (OJ 287, 3C 279, PKS 1510-089, 3C 345, BL Lac and 3C 454. Read More


The lightest Kaluza-Klein particle (LKP), which appears in the theory of universal extra dimensions, is one of good candidates for cold dark matter (CDM). When LKP pairs annihilate around the center of the Galaxy where CDM is concentrated, there are some modes which produce electrons and positrons as final products, and we categorize them into two components. One of them is the "Line" component, which directly annihilates into electron--positron pair. Read More


The youngest Galactic supernova remnant (SNR) G1.9+0.3, produced by a (probable) SN Ia that exploded $\sim 1900$ CE, is strongly asymmetric at radio wavelengths, much brighter in the north, but bilaterally symmetric in X-rays. Read More


We provide the quasiclassical derivation of the modified chiral magnetic effect in the case when massless charged fermions moving in external electromagnetic fields interact by electroweak forces with the background matter. In our study we rely on the energy balance between the external electromagnetic field and charged particles. The obtained expression for the electric current along the external magnetic field appears to coincide with our previous results based on the purely quantum approach. Read More


X-ray spectra of accreting pulsars are generally observed to vary with their X-ray luminosity. In particular, the hardness of the X-ray continuum is found to depend on luminosity. In a few sources, the correlation between the energy of the cyclotron resonance scattering feature (CRSF) and the luminosity is clear. Read More


Photon counts statistics have recently been proven to provide a sensitive observable for characterizing gamma-ray source populations and for measuring the composition of the gamma-ray sky. In this work, we generalize the use of the standard 1-point probability distribution function (1pPDF) to decompose the high-latitude gamma-ray emission observed with Fermi-LAT into: (i) point-source contributions, (ii) the Galactic foreground contribution, and (iii) a diffuse isotropic background contribution. We analyze gamma-ray data in five adjacent energy bands between 1 and 171 GeV. Read More


The propagation of cosmic rays in turbulent magnetic fields is a diffusive process driven by the scattering of the charged particles by random magnetic fluctuations. Such fields are usually highly intermittent, consisting of intense magnetic filaments and ribbons surrounded by weaker, unstructured fluctuations. Studies of cosmic ray propagation have largely overlooked intermittency, instead relying on Gaussian random magnetic fields. Read More


Several extensions of the Standard Model contain right-handed (sterile) neutrinos in the GeV-TeV mass range. Due to their mixing with the active neutrinos, they may give rise to novel effects in cosmology, neutrino physics, and collider searches. In addition, right-handed neutrinos can also appear as final states from dark matter annihilations, with important implications for dark matter indirect detection searches. Read More


We use adaptive-mesh magnetohydrodynamic simulations to study the effect of magnetic fields on ram pressure stripping of galaxies in the intracluster medium (ICM). Although the magnetic pressure in typical clusters is not strong enough to affect the gas mass loss rate from galaxies, magnetic fields can affect the morphology of stripped galaxies. ICM magnetic fields are draped around orbiting galaxies and aligned with their stripped tails. Read More


2017Feb
Authors: M. G. Aartsen, M. Ackermann, J. Adams, J. A. Aguilar, M. Ahlers, M. Ahrens, I. Al Samarai, D. Altmann, K. Andeen, T. Anderson, I. Ansseau, G. Anton, M. Archinger, C. Arg/"uelles, J. Auffenberg, S. Axani, X. Bai, S. W. Barwick, V. Baum, R. Bay, J. J. Beatty, J. Becker Tjus, K. -H. Becker, S. BenZvi, D. Berley, E. Bernardini, A. Bernhard, D. Z. Besson, G. Binder, D. Bindig, E. Blaufuss, S. Blot, C. Bohm, M. Börner, F. Bos, D. Bose, S. Böser, O. Botner, J. Braun, L. Brayeur, H. -P. Bretz, S. Bron, A. Burgman, T. Carver, M. Casier, E. Cheung, D. Chirkin, A. Christov, K. Clark, L. Classen, S. Coenders, G. H. Collin, J. M. Conrad, D. F. Cowen, R. Cross, M. Day, J. P. A. M. de André, C. De Clercq, E. del Pino Rosendo, H. Dembinski, S. De Ridder, P. Desiati, K. D. de Vries, G. de Wasseige, M. de With, T. DeYoung, V. di Lorenzo, H. Dujmovic, J. P. Dumm, M. Dunkman, B. Eberhardt, T. Ehrhardt, B. Eichmann, P. Eller, S. Euler, P. A. Evenson, S. Fahey, A. R. Fazely, J. Feintzeig, J. Felde, K. Filimonov, C. Finley, S. Flis, C. -C. Fösig, A. Franckowiak, E. Friedman, T. Fuchs, T. K. Gaisser, J. Gallagher, L. Gerhardt, K. Ghorbani, W. Giang, L. Gladstone, T. Glauch, T. Glüsenkamp, A. Goldschmidt, J. G. Gonzalez, D. Grant, Z. Griffith, C. Haack, A. Hallgren, F. Halzen, E. Hansen, T. Hansmann, K. Hanson, D. Hebecker, D. Heereman, K. Helbing, R. Hellauer, S. Hickford, J. Hignight, G. C. Hill, K. D. Hoffman, R. Hoffmann, K. Hoshina, F. Huang, M. Huber, K. Hultqvist, S. In, A. Ishihara, E. Jacobi, G. S. Japaridze, M. Jeong, K. Jero, B. J. P. Jones, W. Kang, A. Kappes, T. Karg, A. Karle, U. Katz, M. Kauer, A. Keivani, J. L. Kelley, A. Kheirandish, J. Kim, M. Kim, T. Kintscher, J. Kiryluk, T. Kittler, S. R. Klein, G. Kohnen, R. Koirala, H. Kolanoski, R. Konietz, L. Köpke, C. Kopper, S. Kopper, D. J. Koskinen, M. Kowalski, K. Krings, M. Kroll, G. Krückl, C. Krüger, J. Kunnen, S. Kunwar, N. Kurahashi, T. Kuwabara, A. Kyriacou, M. Labare, J. L. Lanfranchi, M. J. Larson, F. Lauber, M. Lesiak-Bzdak, M. Leuermann, L. Lu, J. Lünemann, J. Madsen, G. Maggi, K. B. M. Mahn, S. Mancina, M. Mandelartz, R. Maruyama, K. Mase, R. Maunu, F. McNally, K. Meagher, M. Medici, M. Meier, T. Menne, G. Merino, T. Meures, S. Miarecki, J. Micallef, G. Momenté, T. Montaruli, M. Moulai, R. Nahnhauer, U. Naumann, G. Neer, H. Niederhausen, S. C. Nowicki, D. R. Nygren, A. Obertacke Pollmann, A. Olivas, A. O'Murchadha, T. Palczewski, H. Pandya, D. V. Pankova, P. Peiffer, Ö. Penek, J. A. Pepper, C. Pérez de los Heros, D. Pieloth, E. Pinat, P. B. Price, G. T. Przybylski, M. Quinnan, C. Raab, L. Rädel, M. Rameez, K. Rawlins, R. Reimann, B. Relethford, M. Relich, E. Resconi, W. Rhode, M. Richman, B. Riedel, S. Robertson, M. Rongen, C. Rott, T. Ruhe, D. Ryckbosch, D. Rysewyk, L. Sabbatini, S. E. Sanchez Herrera, A. Sandrock, J. Sandroos, S. Sarkar, K. Satalecka, P. Schlunder, T. Schmidt, S. Schoenen, S. Schöneberg, L. Schumacher, D. Seckel, S. Seunarine, D. Soldin, M. Song, G. M. Spiczak, C. Spiering, J. Stachurska, T. Stanev, A. Stasik, J. Stettner, A. Steuer, T. Stezelberger, R. G. Stokstad, A. Stößl, R. Ström, N. L. Strotjohann, G. W. Sullivan, M. Sutherland, H. Taavola, I. Taboada, J. Tatar, F. Tenholt, S. Ter-Antonyan, A. Terliuk, G. Tešić, S. Tilav, P. A. Toale, M. N. Tobin, S. Toscano, D. Tosi, M. Tselengidou, C. F. Tung, A. Turcati, E. Unger, M. Usner, J. Vandenbroucke, N. van Eijndhoven, S. Vanheule, M. van Rossem, J. van Santen, M. Vehring, M. Voge, E. Vogel, M. Vraeghe, C. Walck, A. Wallace, M. Wallraff, N. Wandkowsky, A. Waza, Ch. Weaver, M. J. Weiss, C. Wendt, S. Westerhoff, B. J. Whelan, S. Wickmann, K. Wiebe, C. H. Wiebusch, L. Wille, D. R. Williams, L. Wills, M. Wolf, T. R. Wood, E. Woolsey, K. Woschnagg, D. L. Xu, X. W. Xu, Y. Xu, J. P. Yanez, G. Yodh, S. Yoshida, M. Zoll, K. Z. Stanek, B. J. Shappee, C. S. Kochanek, T. W. -S. Holoien, J. L. Prieto, D. B. Fox, J. J. DeLaunay, C. F. Turley, S. D. Barthelmy, A. Y. Lien, P. Mészáros, K. Murase, D. Kocevski, R. Buehler, M. Giomi, J. L. Racusin, A. Albert, R. Alfaro, C. Alvarez, J. D. Álvarez, R. Arceo, J. C. Arteaga-Velázquez, H. A. Ayala Solares, E. Belmont-Moreno, A. Bernal, C. Brisbois, K. S. Caballero-Mora, T. Capistrán, A. Carramiñana, S. Casanova, M. Castillo, U. Cotti, E. de la Fuente, S. Coutino de León, C. De León, R. Diaz Hernandez, B. L. Dingus, M. A. DuVernois, J. C. Díaz-Vélez, D. W. Fiorino, N. Fraija, J. A. García-González, M. Gerhardt, A. González Muñoz, M. M. González, J. A. Goodman, Z. Hampel-Arias, J. P. Harding, S. Hernandez, C. M. Hui, P. Hüntemeyer, A. Iriarte, A. Jardin-Blicq, V. Joshi, S. Kaufmann, A. Lara, R. J. Lauer, W. H. Lee, D. Lennarz, H. León Vargas, J. T. Linnemann, G. Luis Raya, R. Luna-García, R. López-Coto, K. Malone, S. S. Marinelli, O. Martinez, I. Martinez-Castellanos, J. Martínez-Castro, H. Martínez-Huerta, J. A. Matthews, E. Moreno, M. Mostafá, L. Nellen, M. Newbold, M. U. Nisa, R. Pelayo, J. Pretz, E. G. Pérez-Pérez, Z. Ren, C. D. Rho, C. Rivière, D. Rosa-González, M. Rosenberg, F. Salesa Greus, A. Sandoval, M. Schneider, H. Schoorlemmer, G. Sinnis, A. J. Smith, R. W. Springer, P. Surajbali, O. Tibolla, K. Tollefson, I. Torres, L. Villaseñor, T. Weisgarber, I. G. Wisher, J. Wood, T. Yapici, A. Zepeda, H. Zhou, I. Arcavi, G. Hosseinzadeh, D. A. Howell, S. Valenti, C. McCully, V. M. Lipunov, E. S. Gorbovskoy, N. V. Tiurina, P. V. Balanutsa, A. S. Kuznetsov, V. G. Kornilov, V. Chazov, N. M. Budnev, O. A. Gress, K. I. Ivanov, A. G. Tlatov, R. Rebolo Lopez, M. Serra-Ricart, P. A. Evans, J. A. Kennea, N. Gehrels, J. P. Osborne, K. L. Page, A. U. Abeysekara, A. Archer, W. Benbow, R. Bird, T. Brantseg, V. Bugaev, J. V Cardenzana, M. P. Connolly, W. Cui, A. Falcone, Q. Feng, J. P. Finley, H. Fleischhack, L. Fortson, A. Furniss, S. Griffin, J. Grube, M. Hütten, O. Hervet, J. Holder, G. Hughes, T. B. Humensky, C. A. Johnson, P. Kaaret, P. Kar, N. Kelley-Hoskins, M. Kertzman, M. Krause, S. Kumar, M. J. Lang, T. T. Y. Lin, S. McArthur, P. Moriarty, R. Mukherjee, D. Nieto, R. A. Ong, A. N. Otte, M. Pohl, A. Popkow, E. Pueschel, J. Quinn, K. Ragan, P. T. Reynolds, G. T. Richards, E. Roache, C. Rulten, I. Sadeh, M. Santander, G. H. Sembroski, D. Staszak, S. Trépanier, J. Tyler, S. P. Wakely, A. Weinstein, P. Wilcox, A. Wilhelm, D. A. Williams, B. Zitzer, E. Bellm, Z. Cano, A. Gal-Yam, D. A. Kann, E. O. Ofek, M. Rigault, M. Soumagnac

On February 17 2016, the IceCube real-time neutrino search identified, for the first time, three muon neutrino candidates arriving within 100 s of each other which are consistent with a point source origin. Such a triplet is expected only once every 13.7 years as a random coincidence of background events. Read More


Since the beginning of the new millennium, more than 100 $z\sim 6$ quasars have been discovered through several surveys and followed-up with multi-wavelength observations. These data provided a large amount of information on the growth of supermassive black holes at the early epochs, the properties of quasar host galaxies and the joint formation and evolution of these massive systems. We review the properties of the highest-$z$ quasars known so far, especially focusing on some of the most recent results obtained in (sub-)millimeter bands. Read More


Multi-frequency gravitational wave (GW) observations are useful probes of the formation processes of coalescing stellar-mass binary black holes (BBHs). We discuss the phase drift in the GW inspiral waveform of the merging BBH caused by its center-of-mass acceleration. The acceleration strongly depends on the location where a BBH forms within a galaxy, allowing observations of the early inspiral phase of LIGO-like BBH mergers by the Laser Interferometer Space Antenna (LISA) to test the formation mechanism. Read More


We study the QCD phase diagram using a non-local SU(3) NJL model with vector interactions among quarks. We analyze several thermodynamic quantities such as entropy and specific heat, and study the influence of vector interactions on the thermodynamic properties of quark matter. Upon imposing electric charge neutrality and baryon number conservation on the field equations, we compute models for the equation of state of the inner cores of proto-neutron stars providing a non-local treatment of quark matter for astrophysics. Read More


The jets from active galactic nuclei exhibit stability which seems to be far superior compared to that of terrestrial and laboratory jets. They manage to propagate over distances up to a billion of initial jet radii. Yet this may not be an indication of some exotic physics but mainly a reflection of the specific environment these jets propagate through. Read More


Every observation of astrophysical objects involving a spectrum requires atomic data for the interpretation of line fluxes, line ratios and ionization state of the emitting plasma. One of the processes which determines it is collisional ionization. In this study an update of the direct ionization (DI) and excitation-autoionization (EA) processes is discussed for the H to Zn-like isoelectronic sequences. Read More


We present the first extensive X-ray study of the North-America and Pelican star-forming region (NGC7000/IC5070), with the aim of finding and characterizing its young stellar population. X-ray data from Chandra (four pointings) and XMM-Newton (seven pointings) were reduced and source detection was performed on each image. We complement the X-ray data with optical and near-IR data from the IPHAS, UKIDSS, and 2MASS catalogs, and with other published optical and Spitzer IR data. Read More


Misaligned AGN (MAGNs), i.e., radio-loud AGNs with the jet not pointing directly towards us, represent a new class of GeV emitters revealed by the Fermi space telescope. Read More


Fast-declining Type Ia supernovae (SN Ia) separate into two categories based on their bolometric and near-infrared (NIR) properties. The peak bolometric luminosity ($\mathrm{L_{max}}$), the phase of the first maximum relative to the optical, the NIR peak luminosity and the occurrence of a second maximum in the NIR distinguish a group of very faint SN Ia. Fast-declining supernovae show a large range of peak bolometric luminosities ($\mathrm{L_{max}}$ differing by up to a factor of $\sim$ 8). Read More


The observations of the prompt emission of gamma ray bursts (GRB) by GLAST Burst Monitor (GBM), on board Fermi Gamma-ray Space Telescope, suggest the presence of a significant thermal spectral component, whose origin is not well understood. Recently, it has been shown that for long duration GRBs, the spectral width as defined as the logarithm of the ratio of the energies at which the spectrum falls to half its peak value, lie in the range of 0.84-1. Read More


We analyzed the Suzaku data of M86 and its adjacent regions to study the extended emission around it. The M86 core, the plume, and the tail extending toward the northwest were clearly detected, as well as the extended halo around them. From the position angle $\sim45\deg$ to $\sim275\deg$, the surface brightness distribution of the core and the extended halo was represented relatively well with a single $\beta$-model of $\beta\sim0. Read More


We propose that cosmic-ray PeVatrons are pulsar wind nebulae (PWNe) inside supernova remnants (SNRs). The PWN initially expands into the free expanding stellar ejecta. Then, the PWN catches up with the shocked region of the SNR, where particles can be slightly accelerated by the back and forth motion between the PWN and the SNR, and some particles diffuse into the PWN. Read More


The statistical properties of soft gamma repeater SGR J1550--5418 are investigated carefully. We find that the cumulative distributions of fluence, peak flux and duration can be well fitted by the bent power law, while the cumulative distribution of waiting time follows the simple power law. In particular, the probability density functions of fluctuations of fluence, peak flux, and duration have a sharp peak and fat tails, which can be well fitted by the $q$-Gaussian function. Read More


In this paper, we propose a new scenario in which a rapidly-rotating strongly magnetized pulsar without the associated supernova ejecta produces fast radio bursts (FRBs) repeatedly via some mechanisms, and meanwhile an ultra-relativistic electron/positron pair wind from the pulsar sweeps up its ambient dense interstellar medium, giving rise to a non-relativistic pulsar wind nebula (PWN). We show that the synchrotron radio emission from such a PWN is bright enough to account for the recently-discovered persistent radio source associated with the repeating FRB 121102 in reasonable ranges of the model parameters. In addition, our PWN scenario is consistent with the non-evolution of the dispersion measure inferred from all the repeating bursts observed in four years. Read More


The Principle of Maximum Entropy, a powerful and general method for inferring the distribution function given a set of constraints, is applied to deduce the overall distribution of plasmoids (flux ropes/tubes). The analysis is undertaken for the general 3D case, with mass, total flux and (3D) velocity serving as the variables of interest, on account of their physical and observational relevance. The distribution functions for the mass, width, total flux and helicity exhibit a power-law behavior with exponents of $-4/3$, $-2$, $-3$ and $-2$ respectively for small values, whilst all of them display an exponential falloff for large values. Read More


A model of the generation of a magnetic field in a neutron star is developed, based on an instability of the magnetic field caused by the electroweak interaction between electrons and nucleons in nuclear matter. The rate of change of the helicity of the electrons as they scatter on protons in the dense matter of a neutron star is calculated with the help of methods of quantum field theory. The influence of the electroweak interaction between electrons and background nucleons on the process of change of the helicity is examined. Read More


Blazars are an extreme subclass of active galactic nuclei. Their rapid variability, luminous brightness, superluminal motion, and high and variable polarization are probably due to a beaming effect. However, this beaming factor (or Doppler factor) is very difficult to measure. Read More


Variability is one of the extreme observational properties of BL Lacertae objects. AO 0235+164 is a well studied BL Lac through the whole electro-magnetic wavebands. In the present work, we show its optical R band photometric observations carried out during the period of Nov, 2006 to Dec. Read More