TY - JOUR A1 - Sushch, Iurii A1 - Brose, Robert A1 - Pohl, Martin T1 - Modeling of the spatially resolved nonthermal emission from the Vela Jr. supernova remnant JF - Astronomy and astrophysics : an international weekly journal N2 - Vela Jr. (RX J0852.0-4622) is one of just a few known supernova remnants (SNRs) with a resolved shell across the whole electromagnetic spectrum from radio to very-high-energy (>100 GeV; VHE) gamma-rays. Its proximity and large size allow for detailed spatially resolved observations of the source, making Vela Jr. one of the primary sources used for the study of particle acceleration and emission mechanisms in SNRs. High-resolution X-ray observations reveal a steepening of the spectrum toward the interior of the remnant. In this study we aim for a self-consistent radiation model of Vela Jr. which at the same time would explain the broadband emission from the source and its intensity distribution. We solve the full particle transport equation combined with the high-resolution one-dimensional (1D) hydrodynamic simulations (using Pluto code) and subsequently calculate the radiation from the remnant. The equations are solved in the test particle regime. We test two models for the magnetic field profile downstream of the shock: damped magnetic field, which accounts for the damping of strong magnetic turbulence downstream, and transported magnetic field. Neither of these scenarios can fully explain the observed radial dependence of the X-ray spectrum under spherical symmetry. We show, however, that the softening of the spectrum and the X-ray intensity profile can be explained under the assumption that the emission is enhanced within a cone. KW - radiation mechanisms: non-thermal KW - acceleration of particles KW - cosmic rays KW - ISM: supernova remnants KW - X-rays: individuals: Vela Jr (RX J08520-4622) KW - shock waves Y1 - 2018 U6 - https://doi.org/10.1051/0004-6361/201832879 SN - 1432-0746 SN - 0004-6361 VL - 618 PB - EDP Sciences CY - Les Ulis ER - TY - JOUR A1 - Ahnen, M. L. A1 - Ansoldi, S. A1 - Antonelli, L. A. A1 - Arcaro, C. A1 - Babic, A. A1 - Banerjee, B. A1 - Bangale, P. A1 - Barres de Almeida, U. A1 - Barrio, J. A. A1 - Gonzalez, J. Becerra A1 - Bednarek, W. A1 - Bernardini, E. A1 - Berti, A. A1 - Bhattacharyya, W. A1 - Blanch, O. A1 - Bonnoli, G. A1 - Carosi, R. A1 - Carosi, A. A1 - Chatterjee, A. A1 - Colak, S. M. A1 - Colin, P. A1 - Colombo, E. A1 - Contreras, J. L. A1 - Cortina, J. A1 - Covino, S. A1 - Cumani, P. A1 - Da Vela, P. A1 - Dazzi, F. A1 - De Angelis, A. A1 - De Lotto, B. A1 - Delfino, M. A1 - Delgado, Jose Miguel Martins A1 - Di Pierro, F. A1 - Doert, M. A1 - Dominguez, A. A1 - Prester, D. Dominis A1 - Doro, M. A1 - Glawion, D. Eisenacher A1 - Engelkemeier, M. A1 - Ramazani, V. Fallah A1 - Fernandez-Barral, A. A1 - Fidalgo, D. A1 - Fonseca, M. V. A1 - Font, L. A1 - Fruck, C. A1 - Galindo, D. A1 - Lopez, R. J. Garcia A1 - Garczarczyk, M. A1 - Gaug, M. A1 - Giammaria, P. A1 - Godinovic, N. A1 - Gora, D. A1 - Guberman, D. A1 - Hadasch, D. A1 - Hahn, A. A1 - Hassan, T. A1 - Hayashida, M. A1 - Herrera, J. A1 - Hose, J. A1 - Hrupec, D. A1 - Ishio, K. A1 - Konno, Y. A1 - Kubo, H. A1 - Kushida, J. A1 - Kuvezdic, D. A1 - Lelas, D. A1 - Lindfors, E. A1 - Lombardi, S. A1 - Longo, F. A1 - Lopez, M. A1 - Maggio, C. A1 - Majumdar, P. A1 - Makariev, M. A1 - Maneva, G. A1 - Manganaro, M. A1 - Maraschi, L. A1 - Mariotti, M. A1 - Martinez, M. A1 - Mazin, D. A1 - Menzel, U. A1 - Minev, M. A1 - Miranda, J. M. A1 - Mirzoyan, R. A1 - Moralejo, A. A1 - Moreno, V. A1 - Moretti, E. A1 - Nagayoshi, T. A1 - Neustroev, V. A1 - Niedzwiecki, A. A1 - Nievas Rosillo, M. A1 - Nigro, C. A1 - Nilsson, K. A1 - Ninci, D. A1 - Nishijima, K. A1 - Noda, K. A1 - Nogues, L. A1 - Paiano, S. A1 - Palacio, J. A1 - Paneque, D. A1 - Paoletti, R. A1 - Paredes, J. M. A1 - Pedaletti, G. A1 - Peresano, M. A1 - Perri, L. A1 - Persic, M. A1 - Moroni, P. G. Prada A1 - Prandini, E. A1 - Puljak, I. A1 - Garcia, J. R. A1 - Reichardt, I. A1 - Ribo, M. A1 - Rico, J. A1 - Righi, C. A1 - Rugliancich, A. A1 - Saito, T. A1 - Satalecka, K. A1 - Schroeder, S. A1 - Schweizer, T. A1 - Shore, S. N. A1 - Sitarek, J. A1 - Snidaric, I. A1 - Sobczynska, D. A1 - Stamerra, A. A1 - Strzys, M. A1 - Suric, T. A1 - Takalo, L. A1 - Tavecchio, F. A1 - Temnikov, P. A1 - Terzic, T. A1 - Teshima, M. A1 - Torres-Alba, N. A1 - Treves, A. A1 - Tsujimoto, S. A1 - Vanzo, G. A1 - Vazquez Acosta, M. A1 - Vovk, I. A1 - Ward, J. E. A1 - Will, M. A1 - Zaric, D. A1 - Arbet-Engels, A. A1 - Baack, D. A1 - Balbo, M. A1 - Biland, A. A1 - Blank, M. A1 - Bretz, T. A1 - Bruegge, K. A1 - Bulinski, M. A1 - Buss, J. A1 - Dmytriiev, A. A1 - Dorner, D. A1 - Einecke, S. A1 - Elsaesser, D. A1 - Herbst, T. A1 - Hildebrand, D. A1 - Kortmann, L. A1 - Linhoff, L. A1 - Mahlke, M. A1 - Mannheim, K. A1 - Mueller, S. A. A1 - Neise, D. A1 - Neronov, A. A1 - Noethe, M. A1 - Oberkirch, J. A1 - Paravac, A. A1 - Rhode, W. A1 - Schleicher, B. A1 - Schulz, F. A1 - Sedlaczek, K. A1 - Shukla, A. A1 - Sliusar, V. A1 - Walter, R. A1 - Archer, A. A1 - Benbow, W. A1 - Bird, R. A1 - Brose, Robert A1 - Buckley, J. H. A1 - Bugaev, V. A1 - Christiansen, J. L. A1 - Cui, W. A1 - Daniel, M. K. A1 - Falcone, A. A1 - Feng, Q. A1 - Finley, J. P. A1 - Gillanders, G. H. A1 - Gueta, O. A1 - Hanna, D. A1 - Hervet, O. A1 - Holder, J. A1 - Hughes, G. A1 - Huetten, M. A1 - Humensky, T. B. A1 - Johnson, C. A. A1 - Kaaret, P. A1 - Kar, P. A1 - Kelley-Hoskins, N. A1 - Kertzman, M. A1 - Kieda, D. A1 - Krause, M. A1 - Krennrich, F. A1 - Kumar, S. A1 - Lang, M. J. A1 - Lin, T. T. Y. A1 - Maier, G. A1 - McArthur, S. A1 - Moriarty, P. A1 - Mukherjee, R. A1 - Ong, R. A. A1 - Otte, A. N. A1 - Park, N. A1 - Petrashyk, A. A1 - Pichel, A. A1 - Pohl, Martin A1 - Quinn, J. A1 - Ragan, K. A1 - Reynolds, P. T. A1 - Richards, G. T. A1 - Roache, E. A1 - Rovero, A. C. A1 - Rulten, C. A1 - Sadeh, I. A1 - Santander, M. A1 - Sembroski, G. H. A1 - Shahinyan, K. A1 - Sushch, Iurii A1 - Tyler, J. A1 - Wakely, S. P. A1 - Weinstein, A. A1 - Wells, R. M. A1 - Wilcox, P. A1 - Wilhel, A. A1 - Williams, D. A. A1 - Williamson, T. J. A1 - Zitzer, B. A1 - Perri, M. A1 - Verrecchia, F. A1 - Leto, C. A1 - Villata, M. A1 - Raiteri, C. M. A1 - Jorstad, S. G. A1 - Larionov, V. M. A1 - Blinov, D. A. A1 - Grishina, T. S. A1 - Kopatskaya, E. N. A1 - Larionova, E. G. A1 - Nikiforova, A. A. A1 - Morozova, D. A. A1 - Troitskaya, Yu. V. A1 - Troitsky, I. S. A1 - Kurtanidze, O. M. A1 - Nikolashvili, M. G. A1 - Kurtanidze, S. O. A1 - Kimeridze, G. N. A1 - Chigladze, R. A. A1 - Strigachev, A. A1 - Sadun, A. C. T1 - Extreme HBL behavior of Markarian 501 during 2012 JF - Astronomy and astrophysics : an international weekly journal / European Southern Observatory (ESO) N2 - Aims. We aim to characterize the multiwavelength emission from Markarian 501 (Mrk 501), quantify the energy-dependent variability, study the potential multiband correlations, and describe the temporal evolution of the broadband emission within leptonic theoretical scenarios. Methods. We organized a multiwavelength campaign to take place between March and July of 2012. Excellent temporal coverage was obtained with more than 25 instruments, including the MAGIC, FACT and VERITAS Cherenkov telescopes, the instruments on board the Swift and Fermi spacecraft, and the telescopes operated by the GASP-WEBT collaboration. Results. Mrk 501 showed a very high energy (VHE) gamma-ray flux above 0.2 TeV of similar to 0.5 times the Crab Nebula flux (CU) for most of the campaign. The highest activity occurred on 2012 June 9, when the VHE flux was similar to 3 CU, and the peak of the high-energy spectral component was found to be at similar to 2 TeV. Both the X-ray and VHE gamma-ray spectral slopes were measured to be extremely hard, with spectral indices <2 during most of the observing campaign, regardless of the X-ray and VHE flux. This study reports the hardest Mrk 501 VHE spectra measured to date. The fractional variability was found to increase with energy, with the highest variability occurring at VHE. Using the complete data set, we found correlation between the X-ray and VHE bands; however, if the June 9 flare is excluded, the correlation disappears (significance <3 sigma) despite the existence of substantial variability in the X-ray and VHE bands throughout the campaign. Conclusions. The unprecedentedly hard X-ray and VHE spectra measured imply that their low- and high-energy components peaked above 5 keV and 0.5 TeV, respectively, during a large fraction of the observing campaign, and hence that Mrk 501 behaved like an extreme high-frequency-peaked blazar (EHBL) throughout the 2012 observing season. This suggests that being an EHBL may not be a permanent characteristic of a blazar, but rather a state which may change over time. The data set acquired shows that the broadband spectral energy distribution (SED) of Mrk 501, and its transient evolution, is very complex, requiring, within the framework of synchrotron self-Compton (SSC) models, various emission regions for a satisfactory description. Nevertheless the one-zone SSC scenario can successfully describe the segments of the SED where most energy is emitted, with a significant correlation between the electron energy density and the VHE gamma-ray activity, suggesting that most of the variability may be explained by the injection of high-energy electrons. The one-zone SSC scenario used reproduces the behavior seen between the measured X-ray and VHE gamma-ray fluxes, and predicts that the correlation becomes stronger with increasing energy of the X-rays. KW - astroparticle physics KW - acceleration of particles KW - radiation mechanisms: non-thermal KW - BL Lacertae objects: general KW - BL Lacertae objects: individual: Mrk501 Y1 - 2018 U6 - https://doi.org/10.1051/0004-6361/201833704 SN - 1432-0746 VL - 620 PB - EDP Sciences CY - Les Ulis ER -