TY - JOUR A1 - Liu, Ruo-Yu A1 - Yan, Huirong A1 - Wang, Xiang-Yu A1 - Shao, Shi A1 - Li, Hui T1 - Gamma-Ray production in the extended halo of the galaxy and possible implications for the origin of galactic cosmic rays JF - The astrophysical journal : an international review of spectroscopy and astronomical physics N2 - Various studies have implied the existence of a gaseous halo around the Galaxy extending out to similar to 100 kpc. Galactic cosmic rays (CRs) that propagate to the halo, either by diffusion or by convection with the possibly existing large-scale Galactic wind, can interact with the gas therein and produce gamma-rays via proton-proton collision. We calculate the CR distribution in the halo and the gamma-ray flux, and explore the dependence of the result on model parameters such as diffusion coefficient, CR luminosity, and CR spectral index. We find that the current measurement of isotropic gamma-ray background (IGRB) at less than or similar to TeV with the Fermi Large Area Telescope already approaches a level that can provide interesting constraints on the properties of Galactic CR (e.g., with CR luminosity L-CR <= 1041 erg s(-1)). We also discuss the possibilities of the Fermi bubble and IceCube neutrinos originating from the proton-proton collision between CRs and gas in the halo, as well as the implication of our results for the baryon budget of the hot circumgalactic medium of our Galaxy. Given that the isotropic gamma-ray background is likely to be dominated by unresolved extragalactic sources, future telescopes may extract more individual sources from the IGRB, and hence put even more stringent restrictions on the relevant quantities (such as Galactic CR luminosity and baryon budget in the halo) in the presence of a turbulent halo that we consider. KW - cosmic rays KW - Galaxy: halo KW - gamma rays: diffuse background KW - neutrinos Y1 - 2019 U6 - https://doi.org/10.3847/1538-4357/aaf567 SN - 0004-637X SN - 1538-4357 VL - 871 IS - 1 PB - IOP Publ. Ltd. CY - Bristol ER - TY - JOUR A1 - Lebiga, O. A1 - Santos-Lima, Reinaldo A1 - Yan, Huirong T1 - Kinetic-MHD simulations of gyroresonance instability driven by CR pressure anisotropy JF - Monthly notices of the Royal Astronomical Society N2 - The transport of cosmic rays (CRs) is crucial for the understanding of almost all high-energy phenomena. Both pre-existing large-scale magnetohydrodynamic (MHD) turbulence and locally generated turbulence through plasma instabilities are important for the CR propagation in astrophysical media. The potential role of the resonant instability triggered by CR pressure anisotropy to regulate the parallel spatial diffusion of low-energy CRs (less than or similar to 100 GeV) in the interstellar and intracluster medium of galaxies has been shown in previous theoretical works. This work aims to study the gyroresonance instability via direct numerical simulations, in order to access quantitatively the wave-particle scattering rates. For this, we employ a 1D PIC-MHD code to follow the growth and saturation of the gyroresonance instability. We extract from the simulations the pitch-angle diffusion coefficient D-mu mu produced by the instability during the linear and saturation phases, and a very good agreement (within a factor of 3) is found with the values predicted by the quasi-linear theory (QLT). Our results support the applicability of the QLT for modelling the scattering of low-energy CRs by the gyroresonance instability in the complex interplay between this instability and the large-scale MHD turbulence. KW - MHD KW - plasmas KW - turbulence KW - cosmic rays Y1 - 2018 U6 - https://doi.org/10.1093/mnras/sty309 SN - 0035-8711 SN - 1365-2966 VL - 476 IS - 2 SP - 2779 EP - 2791 PB - Oxford Univ. Press CY - Oxford ER - TY - JOUR A1 - Warren, Donald C. A1 - Ellison, Donald C. A1 - Barkov, Maxim V. A1 - Nagataki, Shigehiro T1 - Nonlinear Particle Acceleration and Thermal Particles in GRB Afterglows JF - The astrophysical journal : an international review of spectroscopy and astronomical physics N2 - The standard model for GRB afterglow emission treats the accelerated electron population as a simple power law, N(E) proportional to E-p for p greater than or similar to 2. However, in standard Fermi shock acceleration, a substantial fraction of the swept-up particles do not enter the acceleration process at all. Additionally, if acceleration is efficient, then the nonlinear back-reaction of accelerated particles on the shock structure modifies the shape of the nonthermal tail of the particle spectra. Both of these modifications to the standard synchrotron afterglow impact the luminosity, spectra, and temporal variation of the afterglow. To examine the effects of including thermal particles and nonlinear particle acceleration on afterglow emission, we follow a hydrodynamical model for an afterglow jet and simulate acceleration at numerous points during the evolution. When thermal particles are included, we find that the electron population is at no time well fitted by a single power law, though the highest-energy electrons are; if the acceleration is efficient, then the power-law region is even smaller. Our model predicts hard-soft-hard spectral evolution at X-ray energies, as well as an uncoupled X-ray and optical light curve. Additionally, we show that including emission from thermal particles has drastic effects (increases by factors of 100 and 30, respectively) on the observed flux at optical and GeV energies. This enhancement of GeV emission makes afterglow detections by future gamma-ray observatories, such as CTA, very likely. KW - acceleration of particles KW - cosmic rays KW - gamma-ray burst: general KW - shock waves KW - turbulence Y1 - 2017 U6 - https://doi.org/10.3847/1538-4357/aa56c3 SN - 0004-637X SN - 1538-4357 VL - 835 IS - 2 PB - IOP Publ. Ltd. CY - Bristol ER - TY - JOUR A1 - Abdalla, Hassan E. A1 - Abramowski, A. A1 - Aharonian, Felix A. A1 - Benkhali, F. Ait A1 - Akhperjanian, A. G. A1 - Andersson, T. A1 - Anguener, E. O. A1 - Arakawa, M. A1 - Arrieta, M. A1 - Aubert, P. A1 - Backes, M. A1 - Balzer, A. A1 - Barnard, M. A1 - Becherini, Y. A1 - Tjus, J. Becker A1 - Berge, D. A1 - Bernhard, S. A1 - Bernloehr, K. A1 - Blackwell, R. A1 - Boettcher, M. A1 - Boisson, C. A1 - Bolmont, J. A1 - Bonnefoy, S. A1 - Bordas, Pol A1 - Bregeon, J. A1 - Brun, F. A1 - Brun, P. A1 - Bryan, M. A1 - Buechele, M. A1 - Bulik, T. A1 - Capasso, M. A1 - Carr, J. A1 - Casanova, Sabrina A1 - Cerruti, M. A1 - Chakraborty, N. A1 - Chaves, R. C. G. A1 - Chen, A. A1 - Chevalier, J. A1 - Coffaro, M. A1 - Colafrancesco, S. A1 - Cologna, G. A1 - Condon, B. A1 - Conrad, J. A1 - Cui, Y. A1 - Davids, I. D. A1 - Decock, J. A1 - Degrange, B. A1 - Deil, C. A1 - Devin, J. A1 - deWilt, P. A1 - Dirson, L. A1 - Djannati-Atai, A. A1 - Domainko, W. A1 - Donath, A. A1 - Dutson, K. A1 - Dyks, J. A1 - Edwards, T. A1 - Egberts, Kathrin A1 - Eger, P. A1 - Ernenwein, J. -P. A1 - Eschbach, S. A1 - Farnier, C. A1 - Fegan, S. A1 - Fernandes, M. V. A1 - Fiasson, A. A1 - Fontaine, G. A1 - Foerster, A. A1 - Funk, S. A1 - Fuessling, M. A1 - Gabici, S. A1 - Gajdus, M. A1 - Gallant, Y. A. A1 - Garrigoux, T. A1 - Giavitto, G. A1 - Giebels, B. A1 - Glicenstein, J. F. A1 - Gottschall, D. A1 - Goyal, A. A1 - Grondin, M. -H. A1 - Hahn, J. A1 - Haupt, M. A1 - Hawkes, J. A1 - Heinzelmann, G. A1 - Henri, G. A1 - Hermann, G. A1 - Hervet, O. A1 - Hinton, J. A. A1 - Hofmann, W. A1 - Hoischen, Clemens A1 - Holch, T. L. A1 - Holler, M. A1 - Horns, D. A1 - Ivascenko, A. A1 - Iwasaki, H. A1 - Jacholkowska, A. A1 - Jamrozy, M. A1 - Janiak, M. A1 - Jankowsky, D. A1 - Jankowsky, F. A1 - Jingo, M. A1 - Jogler, T. A1 - Jouvin, L. A1 - Jung-Richardt, I. A1 - Kastendieck, M. A. A1 - Katarzynski, K. A1 - Katsuragawa, M. A1 - Katz, U. A1 - Kerszberg, D. A1 - Khangulyan, D. A1 - Khelifi, B. A1 - King, J. A1 - Klepser, S. A1 - Klochkov, D. A1 - Kluzniak, W. A1 - Kolitzus, D. A1 - Komin, Nu. A1 - Kosack, K. A1 - Krakau, S. A1 - Kraus, M. A1 - Krueger, P. P. A1 - Laffon, H. A1 - Lamanna, G. A1 - Lau, J. A1 - Lees, J. -P. A1 - Lefaucheur, J. A1 - Lefranc, V. A1 - Lemiere, A. A1 - Lemoine-Goumard, M. A1 - Lenain, J. -P. A1 - Leser, Eva A1 - Lohse, T. A1 - Lorentz, M. A1 - Liu, R. A1 - Lopez-Coto, R. A1 - Lypova, I. A1 - Marandon, V. A1 - Marcowith, Alexandre A1 - Mariaud, C. A1 - Marx, R. A1 - Maurin, G. A1 - Maxted, N. A1 - Mayer, M. A1 - Meintjes, P. J. A1 - Meyer, M. A1 - Mitche, A. M. W. A1 - Moderski, R. A1 - Mohamed, M. A1 - Mohrmann, L. A1 - Mora, K. A1 - Moulin, Emmanuel A1 - Murach, T. A1 - Nakashima, S. A1 - de Naurois, M. A1 - Niederwanger, F. A1 - Niemiec, J. A1 - Oakes, L. A1 - Odaka, H. A1 - Oettl, S. A1 - Ohm, S. A1 - Ostrowski, M. A1 - Oya, I. A1 - Padovani, M. A1 - Panter, M. A1 - Parsons, R. D. A1 - Pekeur, N. W. A1 - Pelletier, G. A1 - Perennes, C. A1 - Petrucci, P. -O. A1 - Peyaud, B. A1 - Piel, Q. A1 - Pita, S. A1 - Poon, H. A1 - Prokhorov, D. A1 - Prokoph, H. A1 - Puehlhofer, G. A1 - Punch, M. A1 - Quirrenbach, A. A1 - Raab, S. A1 - Reimer, A. A1 - Reimer, O. A1 - Renaud, M. A1 - de los Reyes, R. A1 - Richter, S. A1 - Rieger, F. A1 - Romoli, C. A1 - Rowell, G. A1 - Rudak, B. A1 - Rulten, C. B. A1 - Sahakian, V. A1 - Saito, S. A1 - Salek, D. A1 - Sanchez, D. A. A1 - Santangelo, A. A1 - Sasaki, M. A1 - Schlickeiser, R. A1 - Schuessler, F. A1 - Schulz, A. A1 - Schwanke, U. A1 - Schwemmer, S. A1 - Seglar-Arroyo, M. A1 - Settimo, M. A1 - Seyffert, A. S. A1 - Shafi, N. A1 - Shilon, I. A1 - Simoni, R. A1 - Sol, H. A1 - Spanier, F. A1 - Spengler, G. A1 - Spies, F. A1 - Stawarz, L. A1 - Steenkamp, R. A1 - Stegmann, Christian A1 - Stycz, K. A1 - Sushch, I. A1 - Takahashi, T. A1 - Tavernet, J. -P. A1 - Tavernier, T. A1 - Taylor, A. M. A1 - Terrier, R. A1 - Tibaldo, L. A1 - Tiziani, D. A1 - Tluczykont, M. A1 - Trichard, C. A1 - Tsuji, N. A1 - Tuffs, R. A1 - Uchiyama, Y. A1 - van der Wale, D. J. A1 - van Eldik, C. A1 - van Rensburg, C. A1 - van Soelen, B. A1 - Vasileiadis, G. A1 - Veh, J. A1 - Venter, C. A1 - Viana, A. A1 - Vincent, P. A1 - Vink, J. A1 - Voisin, F. A1 - Voelk, H. J. A1 - Vuillaume, T. A1 - Wadiasingh, Z. A1 - Wagner, S. J. A1 - Wagner, P. A1 - Wagner, R. M. A1 - White, R. A1 - Wierzcholska, A. A1 - Willmann, P. A1 - Woernlein, A. A1 - Wouters, D. A1 - Yang, R. A1 - Zabalza, V. A1 - Zaborov, D. A1 - Zacharias, M. A1 - Zanin, R. A1 - Zdziarski, A. A. A1 - Zech, Alraune A1 - Zefi, F. A1 - Ziegler, A. A1 - Zywucka, N. A1 - Bamba, A. A1 - Fukui, Y. A1 - Sano, H. A1 - Yoshiike, S. T1 - A search for new supernova remnant shells in the Galactic plane with HESS JF - Astronomy and astrophysics : an international weekly journal N2 - A search for new supernova remnants (SNRs) has been conducted using TeV gamma-ray data from the H.E.S.S. Galactic plane survey. As an identification criterion, shell morphologies that are characteristic for known resolved TeV SNRs have been used. Three new SNR candidates were identified in the H.E.S.S. data set with this method. Extensive multiwavelength searches for counterparts were conducted. A radio SNR candidate has been identified to be a counterpart to HESS J1534-571. The TeV source is therefore classified as a SNR. For the other two sources, HESS J1614-518 and HESS J1912 + 101, no identifying counterparts have been found, thus they remain SNR candidates for the time being. TeV-emitting SNRs are key objects in the context of identifying the accelerators of Galactic cosmic rays. The TeV emission of the relativistic particles in the new sources is examined in view of possible leptonic and hadronic emission scenarios, taking the current multiwavelength knowledge into account. KW - astroparticle physics KW - ISM: supernova remnants KW - cosmic rays Y1 - 2018 U6 - https://doi.org/10.1051/0004-6361/201730737 SN - 1432-0746 VL - 612 PB - EDP Sciences CY - Les Ulis ER - TY - JOUR A1 - Abramowski, A. A1 - Aharonian, Felix A. A1 - Benkhali, F. Ait A1 - Akhperjanian, A. G. A1 - Anguener, E. O. A1 - Backes, M. A1 - Balzer, A. A1 - Becherini, Y. A1 - Tjus, J. Becker A1 - Berge, D. A1 - Bernhard, S. A1 - Bernloehr, K. A1 - Birsin, E. A1 - Blackwell, R. A1 - Boettcher, M. A1 - Boisson, C. A1 - Bolmont, J. A1 - Bordas, Pol A1 - Bregeon, J. A1 - Brun, F. A1 - Brun, P. A1 - Bryan, M. A1 - Bulik, T. A1 - Carr, J. A1 - Casanova, Sabrina A1 - Chakraborty, N. A1 - Chalme-Calvet, R. A1 - Chaves, R. C. G. A1 - Chen, A. A1 - Chevalier, J. A1 - Chretien, M. A1 - Colafrancesco, S. A1 - Cologna, G. A1 - Condon, B. A1 - Conrad, J. A1 - Couturier, C. A1 - Cui, Y. A1 - Davids, I. D. A1 - Degrange, B. A1 - Deil, C. A1 - deWilt, P. A1 - Djannati-Atai, A. A1 - Domainko, W. A1 - Donath, A. A1 - Dubus, G. A1 - Dutson, K. A1 - Dyks, J. A1 - Dyrda, M. A1 - Edwards, T. A1 - Egberts, Kathrin A1 - Eger, P. A1 - Ernenwein, J. -P. A1 - Espigat, P. A1 - Farnier, C. A1 - Fegan, S. A1 - Feinstein, F. A1 - Fernandes, M. V. A1 - Fernandez, D. A1 - Fiasson, A. A1 - Fontaine, G. A1 - Foerster, A. A1 - Fuessling, M. A1 - Gabici, S. A1 - Gajdus, M. A1 - Gallant, Y. A. A1 - Garrigoux, T. A1 - Giavitto, G. A1 - Giebels, B. A1 - Glicenstein, J. F. A1 - Gottschall, D. A1 - Goyal, A. A1 - Grondin, M. -H. A1 - Grudzinska, M. A1 - Hadasch, D. A1 - Haeffner, S. A1 - Hahn, J. A1 - Hawkes, J. A1 - Heinzelmann, G. A1 - Henri, G. A1 - Hermann, G. A1 - Hervet, O. A1 - Hillert, A. A1 - Hinton, J. A. A1 - Hofmann, W. A1 - Hofverberg, P. A1 - Hoischen, Clemens A1 - Holler, M. A1 - Horns, D. A1 - Ivascenko, A. A1 - Jacholkowska, A. A1 - Jamrozy, M. A1 - Janiak, M. A1 - Jankowsky, F. A1 - Jung-Richardt, I. A1 - Kastendieck, M. A. A1 - Katarzynski, K. A1 - Katz, U. A1 - Kerszberg, D. A1 - Khelifi, B. A1 - Kieffer, M. A1 - Klepser, S. A1 - Klochkov, D. A1 - Kluzniak, W. A1 - Kolitzus, D. A1 - Komin, Nu. A1 - Kosack, K. A1 - Krakau, S. A1 - Krayzel, F. A1 - Krueger, P. P. A1 - Laffon, H. A1 - Lamanna, G. A1 - Lau, J. A1 - Lefaucheur, J. A1 - Lefranc, V. A1 - Lemiere, A. A1 - Lemoine-Goumard, M. A1 - Lenain, J. -P. A1 - Lohse, T. A1 - Lopatin, A. A1 - Lorentz, M. A1 - Lu, C. -C. A1 - Lui, R. A1 - Marandon, V. A1 - Marcowith, Alexandre A1 - Mariaud, C. A1 - Marx, R. A1 - Maurin, G. A1 - Maxted, N. A1 - Mayer, M. A1 - Meintjes, P. J. A1 - Menzler, U. A1 - Meyer, M. A1 - Mitchell, A. M. W. A1 - Moderski, R. A1 - Mohamed, M. A1 - Mora, K. A1 - Moulin, Emmanuel A1 - Murach, T. A1 - de Naurois, M. A1 - Niemiec, J. A1 - Oakes, L. A1 - Odaka, H. A1 - Oettl, S. A1 - Ohm, S. A1 - Opitz, B. A1 - Ostrowski, M. A1 - Oya, I. A1 - Panter, M. A1 - Parsons, R. D. A1 - Arribas, M. Paz A1 - Pekeur, N. W. A1 - Pelletier, G. A1 - Petrucci, P. -O. A1 - Peyaud, B. A1 - Pita, S. A1 - Poon, H. A1 - Prokhorov, D. A1 - Prokoph, H. A1 - Puehlhofer, G. A1 - Punch, M. A1 - Quirrenbach, A. A1 - Raab, S. A1 - Reichardt, I. A1 - Reimer, A. A1 - Reimer, O. A1 - Renaud, M. A1 - de los Reyes, R. A1 - Rieger, F. A1 - Romoli, C. A1 - Rosier-Lees, S. A1 - Rowell, G. A1 - Rudak, B. A1 - Rulten, C. B. A1 - Sahakian, V. A1 - Salek, D. A1 - Sanchez, D. A. A1 - Santangelo, A. A1 - Sasaki, M. A1 - Schlickeiser, R. A1 - Schuessler, F. A1 - Schulz, A. A1 - Schwanke, U. A1 - Schwemmer, S. A1 - Seyffert, A. S. A1 - Simoni, R. A1 - Sol, H. A1 - Spanier, F. A1 - Spengler, G. A1 - Spies, F. A1 - Stawarz, L. A1 - Steenkamp, R. A1 - Stegmann, Christian A1 - Stinzing, F. A1 - Stycz, K. A1 - Sushch, I. A1 - Tavernet, J. -P. A1 - Tavernier, T. A1 - Taylor, A. M. A1 - Terrier, R. A1 - Tluczykont, M. A1 - Trichard, C. A1 - Tuffs, R. A1 - Valerius, K. A1 - van der Walt, J. A1 - van Eldik, C. A1 - van Soelen, B. A1 - Vasileiadis, G. A1 - Veh, J. A1 - Venter, C. A1 - Viana, A. A1 - Vincent, P. A1 - Vink, J. A1 - Voisin, F. A1 - Voelk, H. J. A1 - Vuillaume, T. A1 - Wagner, S. J. A1 - Wagner, P. A1 - Wagner, R. M. A1 - Weidinger, M. A1 - White, R. A1 - Wierzcholska, A. A1 - Willmann, P. A1 - Woernlein, A. A1 - Wouters, D. A1 - Yang, R. A1 - Zabalza, V. A1 - Zaborov, D. A1 - Zacharias, M. A1 - Zdziarski, A. A. A1 - Zech, Alraune A1 - Zefi, F. A1 - Zywucka, N. T1 - Detailed spectral and morphological analysis of the shell type supernova remnant RCW 86 JF - Astronomy and astrophysics : an international weekly journal N2 - Aims. We aim for an understanding of the morphological and spectral properties of the supernova remnant RCW 86 and for insights into the production mechanism leading to the RCW 86 very high-energy gamma-ray emission. Methods. We analyzed High Energy Spectroscopic System (H.E.S.S.) data that had increased sensitivity compared to the observations presented in the RCW 86 H.E.S.S. discovery publication. Studies of the morphological correlation between the 0.5-1 keV X-ray band, the 2-5 keV X-ray band, radio, and gamma-ray emissions have been performed as well as broadband modeling of the spectral energy distribution with two different emission models. Results. We present the first conclusive evidence that the TeV gamma-ray emission region is shell-like based on our morphological studies. The comparison with 2-5 keV X-ray data reveals a correlation with the 0.4-50 TeV gamma-ray emission. The spectrum of RCW 86 is best described by a power law with an exponential cutoff at E-cut = (3.5 +/- 1.2(stat)) TeV and a spectral index of Gamma approximate to 1.6 +/- 0.2. A static leptonic one-zone model adequately describes the measured spectral energy distribution of RCW 86, with the resultant total kinetic energy of the electrons above 1 GeV being equivalent to similar to 0.1% of the initial kinetic energy of a Type Ia supernova explosion (10(51) erg). When using a hadronic model, a magnetic field of B approximate to 100 mu G is needed to represent the measured data. Although this is comparable to formerly published estimates, a standard E-2 spectrum for the proton distribution cannot describe the gamma-ray data. Instead, a spectral index of Gamma(p) approximate to 1.7 would be required, which implies that similar to 7 x 10(49)/n(cm-3) erg has been transferred into high-energy protons with the effective density n(cm-3) = n/1 cm(-3). This is about 10% of the kinetic energy of a typical Type Ia supernova under the assumption of a density of 1 cm(-3). KW - astroparticle physics KW - gamma rays: general KW - ISM: supernova remnants KW - cosmic rays Y1 - 2018 U6 - https://doi.org/10.1051/0004-6361/201526545 SN - 1432-0746 VL - 612 PB - EDP Sciences CY - Les Ulis ER - TY - JOUR A1 - Abdalla, Hassan E. A1 - Abramowski, A. A1 - Aharonian, Felix A. A1 - Benkhali, F. Ait A1 - Akhperjanian, A. G. A1 - Andersson, T. A1 - Anguener, E. O. A1 - Arakawa, M. A1 - Arrieta, M. A1 - Aubert, P. A1 - Backes, M. A1 - Balzer, A. A1 - Barnard, M. A1 - Becherini, Y. A1 - Tjus, J. Becker A1 - Berge, D. A1 - Bernhard, S. A1 - Bernloehr, K. A1 - Blackwell, R. A1 - Boettcher, M. A1 - Boisson, C. A1 - Bolmont, J. A1 - Bordas, Pol A1 - Bregeon, J. A1 - Brun, F. A1 - Brun, P. A1 - Bryan, M. A1 - Bilchele, M. A1 - Bulik, T. A1 - Capasso, M. A1 - Carr, J. A1 - Casanova, Sabrina A1 - Cerruti, M. A1 - Chakraborty, N. A1 - Chalme-Calvet, R. A1 - Chaves, R. C. G. A1 - Chen, A. A1 - Chevalier, J. A1 - Chretien, M. A1 - Coffaro, M. A1 - Colafrancesco, S. A1 - Cologna, G. A1 - Condon, B. A1 - Conrad, J. A1 - Cui, Y. A1 - Davids, I. D. A1 - Decock, J. A1 - Degrange, B. A1 - Deil, C. A1 - Devin, J. A1 - deWilt, P. A1 - Dirson, L. A1 - Djannati-Atai, A. A1 - Domainko, W. A1 - Donath, A. A1 - Dutson, K. A1 - Dyks, J. A1 - Edwards, T. A1 - Egberts, Kathrin A1 - Eger, P. A1 - Ernenwein, J. -P. A1 - Eschbach, S. A1 - Farnier, C. A1 - Fegan, S. A1 - Fernandes, M. V. A1 - Fiasson, A. A1 - Fontaine, G. A1 - Foerster, A. A1 - Funk, S. A1 - Fuessling, M. A1 - Gabici, S. A1 - Gajdus, M. A1 - Gallant, Y. A. A1 - Garrigoux, T. A1 - Giavitto, G. A1 - Giebels, B. A1 - Glicenstein, J. F. A1 - Gottschall, D. A1 - Goya, A. A1 - Grondin, M. -H. A1 - Hahn, J. A1 - Haupt, M. A1 - Hawkes, J. A1 - Heinzelmann, G. A1 - Henri, G. A1 - Hermann, G. A1 - Hervet, O. A1 - Hinton, J. A. A1 - Hofmann, W. A1 - Hoischen, Clemens A1 - Holler, M. A1 - Horns, D. A1 - Ivascenko, A. A1 - Iwasaki, H. A1 - Jacholkowska, A. A1 - Jamrozy, M. A1 - Janiak, M. A1 - Jankowsky, D. A1 - Jankowsky, F. A1 - Jingo, M. A1 - Jogler, T. A1 - Jouvin, L. A1 - Jung-Richardt, I. A1 - Kastendieck, M. A. A1 - Katarzynski, K. A1 - Katsuragawa, M. A1 - Katz, U. A1 - Kerszberg, D. A1 - Khangulyan, D. A1 - Khelifi, B. A1 - Kieffer, M. A1 - King, J. A1 - Klepser, S. A1 - Klochkov, D. A1 - Kluzniak, W. A1 - Kolitzus, D. A1 - Komin, Nu. A1 - Kosack, K. A1 - Krakau, S. A1 - Kraus, M. A1 - Krueger, P. P. A1 - Laffon, H. A1 - Lamanna, G. A1 - Lau, J. A1 - Lees, J. -P. A1 - Lefaucheur, J. A1 - Lefranc, V. A1 - Lemiere, A. A1 - Lemoine-Goumard, M. A1 - Lenain, J. -P. A1 - Leser, Eva A1 - Lohse, T. A1 - Lorentz, M. A1 - Liu, R. A1 - Lopez-Coto, R. A1 - Lypova, I. A1 - Marandon, V. A1 - Marcowith, Alexandre A1 - Mariaud, C. A1 - Marx, R. A1 - Maurin, G. A1 - Maxted, N. A1 - Mayer, M. A1 - Meintjes, P. J. A1 - Meyer, M. A1 - Mitche, A. M. W. A1 - Moderski, R. A1 - Mohamed, M. A1 - Mohrmann, L. A1 - Mora, K. A1 - Moulin, Emmanuel A1 - Murach, T. A1 - Nakashima, S. A1 - de Naurois, M. A1 - Niederwanger, F. A1 - Niemiec, J. A1 - Oakes, L. A1 - Odaka, H. A1 - Oettl, S. A1 - Ohm, S. A1 - Ostrowski, M. A1 - Oya, I. A1 - Padovani, M. A1 - Panter, M. A1 - Parsons, R. D. A1 - Arribas, M. Paz A1 - Pekeur, N. W. A1 - Pelletier, G. A1 - Perennes, C. A1 - Petrucci, P. -O. A1 - Peyaud, B. A1 - Piel, Q. A1 - Pita, S. A1 - Poon, H. A1 - Prokhorov, D. A1 - Prokoph, H. A1 - Puehlhofer, G. A1 - Punch, M. A1 - Quirrenbach, A. A1 - Raab, S. A1 - Reimer, A. A1 - Reimer, O. A1 - Renaud, M. A1 - de los Reyes, R. A1 - Richter, S. A1 - Rieger, F. A1 - Romoli, C. A1 - Rowell, G. A1 - Rudak, B. A1 - Rulten, C. B. A1 - Sahakian, V. A1 - Saito, S. A1 - Salek, D. A1 - Sanchez, D. A. A1 - Santangelo, A. A1 - Sasaki, M. A1 - Schlickeiser, R. A1 - Schuessler, F. A1 - Schulz, A. A1 - Schwanke, U. A1 - Schwemmer, S. A1 - Seglar-Arroyo, M. A1 - Settimo, M. A1 - Seyffert, A. S. A1 - Shafi, N. A1 - Shilon, I. A1 - Simoni, R. A1 - Sol, H. A1 - Spanier, F. A1 - Spengler, G. A1 - Spies, F. A1 - Stawarz, L. A1 - Steenkamp, R. A1 - Stegmann, Christian A1 - Stycz, K. A1 - Sushch, I. A1 - Takahashi, T. A1 - Tavernet, J. -P. A1 - Tavernier, T. A1 - Taylor, A. M. A1 - Terrier, R. A1 - Tibaldo, L. A1 - Tiziani, D. A1 - Tluczykont, M. A1 - Trichard, C. A1 - Tsuji, N. A1 - Tuffs, R. A1 - Uchiyama, Y. A1 - van der Walt, D. J. A1 - van Eldik, C. A1 - van Rensburg, C. A1 - van Soelen, B. A1 - Vasileiadis, G. A1 - Veh, J. A1 - Venter, C. A1 - Viana, A. A1 - Vincent, P. A1 - Vink, J. A1 - Voisin, F. A1 - Voelk, H. J. A1 - Vuillaume, T. A1 - Wadiasingh, Z. A1 - Wagner, S. J. A1 - Wagner, P. A1 - Wagner, R. M. A1 - White, R. A1 - Wierzcholska, A. A1 - Willmann, P. A1 - Woernlein, A. A1 - Wouters, D. A1 - Yang, R. A1 - Zabalza, V. A1 - Zaborov, D. A1 - Zacharias, M. A1 - Zanin, R. A1 - Zdziarski, A. A. A1 - Zech, Alraune A1 - Zefi, F. A1 - Ziegler, A. A1 - Zywucka, N. T1 - Deeper HESS observations of Vela Junior (RX J0852.0-4622) BT - Morphology studies and resolved spectroscopy JF - Astronomy and astrophysics : an international weekly journal N2 - Aims. We study gamma-ray emission from the shell-type supernova remnant (SNR) RXJ0852.0-4622 to better characterize its spectral properties and its distribution over the SNR. Methods. The analysis of an extended High Energy Spectroscopic System (H.E.S.S.) data set at very high energies (E > 100 GeV) permits detailed studies, as well as spatially resolved spectroscopy, of the morphology and spectrum of the whole RXJ0852.0-4622 region. The H.E.S.S. data are combined with archival data from other wavebands and interpreted in the framework of leptonic and hadronic models. The joint Fermi-LAT-H.E.S.S. spectrum allows the direct determination of the spectral characteristics of the parent particle population in leptonic and hadronic scenarios using only GeV-TeV data. Results. An updated analysis of the H.E.S.S. data shows that the spectrum of the entire SNR connects smoothly to the high-energy spectrum measured by Fermi-LAT. The increased data set makes it possible to demonstrate that the H.E.S.S. spectrum deviates significantly from a power law and is well described by both a curved power law and a power law with an exponential cutoff at an energy of E-cut = (6.7 +/- 1.2(stat) +/- 1.2(syst)) TeV. The joint Fermi-LAT-H.E.S.S. spectrum allows the unambiguous identification of the spectral shape as a power law with an exponential cutoff. No significant evidence is found for a variation of the spectral parameters across the SNR, suggesting similar conditions of particle acceleration across the remnant. A simple modeling using one particle population to model the SNR emission demonstrates that both leptonic and hadronic emission scenarios remain plausible. It is also shown that at least a part of the shell emission is likely due to the presence of a pulsar wind nebula around PSR J0855-4644. KW - astroparticle physics KW - gamma rays: general KW - acceleration of particles KW - cosmic rays KW - ISM: supernova remnants Y1 - 2018 U6 - https://doi.org/10.1051/0004-6361/201630002 SN - 1432-0746 VL - 612 PB - EDP Sciences CY - Les Ulis ER - TY - JOUR A1 - Abdalla, Hassan E. A1 - Abramowski, A. A1 - Aharonian, Felix A. A1 - Benkhali, F. Ait A1 - Akhperjanian, A. G. A1 - Andersson, T. A1 - Anguener, E. O. A1 - Arrieta, M. A1 - Aubert, P. A1 - Backes, M. A1 - Balzer, A. A1 - Barnard, M. A1 - Becherini, Y. A1 - Tjus, J. Becker A1 - Berge, D. A1 - Bernhard, S. A1 - Bernloehr, K. A1 - Blackwell, R. A1 - Boettcher, M. A1 - Boisson, C. A1 - Bolmont, J. A1 - Bordas, Pol A1 - Bregeon, J. A1 - Brun, F. A1 - Brun, P. A1 - Bryan, M. A1 - Bulik, T. A1 - Capasso, M. A1 - Carr, J. A1 - Casanova, Sabrina A1 - Cerruti, M. A1 - Chakraborty, N. A1 - Chalme-Calvet, R. A1 - Chaves, R. C. G. A1 - Chen, A. A1 - Chevalier, J. A1 - Chretien, M. A1 - Colafrancesco, S. A1 - Cologna, G. A1 - Condon, B. A1 - Conrad, J. A1 - Cui, Y. A1 - Davids, I. D. A1 - Decock, J. A1 - Degrange, B. A1 - Dei, C. A1 - Devin, J. A1 - deWilt, P. A1 - Dirson, L. A1 - Djannati-Atai, A. A1 - Domainko, W. A1 - Donath, A. A1 - Dubus, G. A1 - Dutson, K. A1 - Dyks, J. A1 - Edwards, T. A1 - Egberts, Kathrin A1 - Eger, P. A1 - Ernenwein, J. -P. A1 - Eschbach, S. A1 - Farnier, C. A1 - Fegan, S. A1 - Fernandes, M. V. A1 - Fiasson, A. A1 - Fontaine, G. A1 - Foerster, A. A1 - Fukuyama, T. A1 - Funk, S. A1 - Fuessling, M. A1 - Gabici, S. A1 - Gajdus, M. A1 - Gallant, Y. A. A1 - Garrigoux, T. A1 - Giavitto, G. A1 - Giebels, B. A1 - Glicenstein, J. F. A1 - Gottschall, D. A1 - Goyal, A. A1 - Grondin, M. -H. A1 - Hadasch, D. A1 - Hahn, J. A1 - Haupt, M. A1 - Hawkes, J. A1 - Heinzelmann, G. A1 - Henri, G. A1 - Hermann, G. A1 - Hervet, O. A1 - Hinton, J. A. A1 - Hofmann, W. A1 - Hoischen, Clemens A1 - Holler, M. A1 - Horns, D. A1 - Ivascenko, A. A1 - Jacholkowska, A. A1 - Jamrozy, M. A1 - Janiak, M. A1 - Jankowsky, D. A1 - Jankowsky, F. A1 - Jingo, M. A1 - Jogler, T. A1 - Jouvin, L. A1 - Jung-Richardt, I. A1 - Kastendieck, M. A. A1 - Katarzynski, K. A1 - Katz, U. A1 - Kerszberg, D. A1 - Khelifi, B. A1 - Kieffer, M. A1 - King, J. A1 - Klepser, S. A1 - Klochkov, D. A1 - Kluzniak, W. A1 - Kolitzus, D. A1 - Komin, Nu. A1 - Kosack, K. A1 - Krakau, S. A1 - Kraus, M. A1 - Krayzel, F. A1 - Krueger, P. P. A1 - Laffon, H. A1 - Lamanna, G. A1 - Lau, J. A1 - Lees, J. -P. A1 - Lefaucheur, J. A1 - Lefranc, V. A1 - Lemiere, A. A1 - Lemoine-Goumard, M. A1 - Lenain, J. -P. A1 - Leser, Eva A1 - Lohse, T. A1 - Lorentz, M. A1 - Liu, R. A1 - Lopez-Coto, R. A1 - Lypova, I. A1 - Marandon, V. A1 - Marcowith, Alexandre A1 - Mariaud, C. A1 - Marx, R. A1 - Maurin, G. A1 - Maxted, N. A1 - Mayer, M. A1 - Meintjes, P. J. A1 - Meyer, M. A1 - Mitchell, A. M. W. A1 - Moderski, R. A1 - Mohamed, M. A1 - Mohrmann, L. A1 - Mora, K. A1 - Moulin, Emmanuel A1 - Murach, T. A1 - de Naurois, M. A1 - Niederwanger, F. A1 - Niemiec, J. A1 - Oakes, L. A1 - Odaka, H. A1 - Oettl, S. A1 - Ohm, S. A1 - Ostrowski, M. A1 - Oya, I. A1 - Padovani, M. A1 - Panter, M. A1 - Parsons, R. D. A1 - Pekeur, N. W. A1 - Pelletier, G. A1 - Perennes, C. A1 - Petrucci, P. -O. A1 - Peyaud, B. A1 - Piel, Q. A1 - Pita, S. A1 - Poon, H. A1 - Prokhorov, D. A1 - Prokoph, H. A1 - Puehlhofer, G. A1 - Punch, M. A1 - Quirrenbach, A. A1 - Raab, S. A1 - Reimer, A. A1 - Reimer, O. A1 - Renaud, M. A1 - de los Reyes, R. A1 - Rieger, F. A1 - Romoli, C. A1 - Rosier-Lees, S. A1 - Rowell, G. A1 - Rudak, B. A1 - Rulten, C. B. A1 - Sahakian, V. A1 - Salek, D. A1 - Sanchez, D. A. A1 - Santangelo, A. A1 - Sasaki, M. A1 - Schlickeiser, R. A1 - Schuessler, F. A1 - Schulz, A. A1 - Schwanke, U. A1 - Schwemmer, S. A1 - Settimo, M. A1 - Seyffert, A. S. A1 - Shafi, N. A1 - Shilon, I. A1 - Simoni, R. A1 - Sol, H. A1 - Spanie, F. A1 - Spengler, G. A1 - Spies, F. A1 - Stawarz, L. A1 - Steenkamp, R. A1 - Stegmann, Christian A1 - Stinzing, F. A1 - Stycz, K. A1 - Sushch, I. A1 - Takahashi, T. A1 - Tavernet, J. -P. A1 - Tavernier, T. A1 - Taylor, A. M. A1 - Terrier, R. A1 - Tibaldo, L. A1 - Tiziani, D. A1 - Tluczykont, M. A1 - Trichard, C. A1 - Tuffs, R. A1 - Uchiyama, Y. A1 - van der Walt, D. J. A1 - van Edik, C. A1 - van Rensburg, C. A1 - van Soelen, B. A1 - Vasileiadis, G. A1 - Veh, J. A1 - Venter, C. A1 - Viana, A. A1 - Vincent, P. A1 - Vink, J. A1 - Voisin, F. A1 - Voelk, H. J. A1 - Volpe, F. A1 - Vuillaume, T. A1 - Wadiasingh, Z. A1 - Wagner, S. J. A1 - Wagner, P. A1 - Wagner, R. M. A1 - White, R. A1 - Wierzcholska, A. A1 - Willmann, P. A1 - Woernlein, A. A1 - Wouters, D. A1 - Yang, R. A1 - Zabalza, V. A1 - Zaborov, D. A1 - Zacharias, M. A1 - Zdziarski, A. A. A1 - Zech, Alraune A1 - Zefi, F. A1 - Ziegler, A. A1 - Zywucka, N. T1 - HESS observations of RX J1713.7-3946 with improved angular and spectral resolution BT - Evidence for gamma-ray emission extending beyond the X-ray emitting shell JF - Astronomy and astrophysics : an international weekly journal KW - acceleration of particles KW - cosmic rays KW - ISM: supernova remnants KW - gamma rays: general KW - astroparticle physic Y1 - 2018 U6 - https://doi.org/10.1051/0004-6361/201629790 SN - 1432-0746 VL - 612 PB - EDP Sciences CY - Les Ulis ER - TY - JOUR A1 - Abdalla, Hassan E. A1 - Abramowski, A. A1 - Aharonian, Felix A. A1 - Benkhali, F. Ait A1 - Angüner, Ekrem Oǧuzhan A1 - Arakawa, M. A1 - Armand, C. A1 - Arrieta, M. A1 - Backes, M. A1 - Balzer, A. A1 - Barnard, M. A1 - Becherini, Y. A1 - Tjus, J. Becker A1 - Berge, D. A1 - Bernhard, S. A1 - Bernloehr, K. A1 - Blackwell, R. A1 - Boettcher, M. A1 - Boisson, C. A1 - Bolmont, J. A1 - Bonnefoy, S. A1 - Bordas, Pol A1 - Bregeon, J. A1 - Brun, F. A1 - Brun, P. A1 - Bryan, M. A1 - Buechele, M. A1 - Bulik, T. A1 - Capasso, M. A1 - Caroff, S. A1 - Carosi, A. A1 - Casanova, Sabrina A1 - Cerruti, M. A1 - Chakraborty, N. A1 - Chaves, R. C. G. A1 - Chen, A. A1 - Chevalier, J. A1 - Colafrancesco, S. A1 - Condon, B. A1 - Conrad, J. A1 - Davids, I. D. A1 - Decock, J. A1 - Deil, C. A1 - Devin, J. A1 - deWilt, P. A1 - Dirson, L. A1 - Djannati-Atai, A. A1 - Donath, A. A1 - Dyks, J. A1 - Edwards, T. A1 - Egberts, Kathrin A1 - Emery, G. A1 - Ernenwein, J. -P. A1 - Eschbach, S. A1 - Farnier, C. A1 - Fegan, S. A1 - Fernandes, M. V. A1 - Fiasson, A. A1 - Fontaine, G. A1 - Funk, S. A1 - Fuessling, M. A1 - Gabici, S. A1 - Gallant, Y. A. A1 - Garrigoux, T. A1 - Gate, F. A1 - Giavitto, G. A1 - Glawion, D. A1 - Glicenstein, J. F. A1 - Gottschall, D. A1 - Grondin, M. -H. A1 - Hahn, J. A1 - Haupt, M. A1 - Hawkes, J. A1 - Heinzelmann, G. A1 - Henri, G. A1 - Hermann, G. A1 - Hinton, J. A. A1 - Hofmann, W. A1 - Hoischen, Clemens A1 - Holch, T. L. A1 - Holler, M. A1 - Horns, D. A1 - Ivascenko, A. A1 - Iwasaki, H. A1 - Jacholkowska, A. A1 - Jamrozy, M. A1 - Jankowsky, D. A1 - Jankowsky, F. A1 - Jingo, M. A1 - Jouvin, L. A1 - Jung-Richardt, I. A1 - Kastendieck, M. A. A1 - Katarzynski, K. A1 - Katsuragawa, M. A1 - Katz, U. A1 - Kerszberg, D. A1 - Khangulyan, D. A1 - Khelifi, B. A1 - King, J. A1 - Klepser, S. A1 - Klochkov, D. A1 - Kluzniak, W. A1 - Komin, Nu. A1 - Kosack, K. A1 - Krakau, S. A1 - Kraus, M. A1 - Kruger, P. P. A1 - Laffon, H. A1 - Lamanna, G. A1 - Lau, J. A1 - Lefaucheur, J. A1 - Lemiere, A. A1 - Lemoine-Goumard, M. A1 - Lenain, J. -P. A1 - Leser, Eva A1 - Lohse, T. A1 - Lorentz, M. A1 - Liu, R. A1 - Lopez-Coto, R. A1 - Lypova, I. A1 - Malyshev, D. A1 - Marandon, V. A1 - Marcowith, Alexandre A1 - Mariaud, C. A1 - Marx, R. A1 - Maurin, G. A1 - Maxted, N. A1 - Mayer, M. A1 - Meintjes, P. J. A1 - Meyer, M. A1 - Mitchell, A. M. W. A1 - Moderski, R. A1 - Mohamed, M. A1 - Mohrmann, L. A1 - Mora, K. A1 - Moulin, Emmanuel A1 - Murach, T. A1 - Nakashima, S. A1 - de Naurois, M. A1 - Ndiyavala, H. A1 - Niederwanger, F. A1 - Niemiec, J. A1 - Oakes, L. A1 - Odaka, H. A1 - Ohm, S. A1 - Ostrowski, M. A1 - Oya, I. A1 - Padovani, M. A1 - Panter, M. A1 - Parsons, R. D. A1 - Pekeur, N. W. A1 - Pelletier, G. A1 - Perennes, C. A1 - Petrucci, P. -O. A1 - Peyaud, B. A1 - Piel, Q. A1 - Pita, S. A1 - Poireau, V. A1 - Prokhorov, D. A. A1 - Prokoph, H. A1 - Puehlhofer, G. A1 - Punch, M. A1 - Quirrenbach, A. A1 - Raab, S. A1 - Rauth, R. A1 - Reimer, A. A1 - Reimer, O. A1 - Renaud, M. A1 - de los Reyes, R. A1 - Rieger, F. A1 - Rinchiuso, L. A1 - Romoli, C. A1 - Rowell, G. A1 - Rudak, B. A1 - Rulten, C. B. A1 - Sahakian, V. A1 - Saito, S. A1 - Sanchez, D. A. A1 - Santangelo, A. A1 - Sasaki, M. A1 - Schlickeiser, R. A1 - Schussler, F. A1 - Schulz, A. A1 - Schwanke, U. A1 - Schwemmer, S. A1 - Seglar-Arroyo, M. A1 - Seyffert, A. S. A1 - Shafi, N. A1 - Shilon, I. A1 - Shiningayamwe, K. A1 - Simoni, R. A1 - Sol, H. A1 - Spanier, F. A1 - Spir-Jacob, M. A1 - Stawarz, L. A1 - Steenkamp, R. A1 - Stegmann, Christian A1 - Steppa, Constantin Beverly A1 - Sushch, I. A1 - Takahashi, T. A1 - Tavernet, J. -P. A1 - Tavernier, T. A1 - Taylor, A. M. A1 - Terrier, R. A1 - Tibaldo, L. A1 - Tiziani, D. A1 - Tluczykont, M. A1 - Trichard, C. A1 - Tsirou, M. A1 - Tsuji, N. A1 - Tuffs, R. A1 - Uchiyama, Y. A1 - van der Walt, D. J. A1 - van Eldik, C. A1 - van Rensburg, C. A1 - van Soelen, B. A1 - Vasileiadis, G. A1 - Veh, J. A1 - Venter, C. A1 - Viana, A. A1 - Vincent, P. A1 - Vink, J. A1 - Voisin, F. A1 - Voelk, H. J. A1 - Vuillaume, T. A1 - Wadiasingh, Z. A1 - Wagner, S. J. A1 - Wagner, P. A1 - Wagner, R. M. A1 - White, R. A1 - Wierzcholska, A. A1 - Willmann, P. A1 - Woernlein, A. A1 - Wouters, D. A1 - Yang, R. A1 - Zaborov, D. A1 - Zacharias, M. A1 - Zanin, R. A1 - Zdziarski, A. A. A1 - Zech, Alraune A1 - Zefi, F. A1 - Ziegler, A. A1 - Zorn, J. A1 - Zywucka, N. A1 - Enokiya, R. A1 - Fukui, Y. A1 - Hayakawa, T. A1 - Okuda, T. A1 - Torii, K. A1 - Yamamoto, H. T1 - HESS J1741-302: a hidden accelerator in the Galactic plane JF - Astronomy and astrophysics : an international weekly journal N2 - The H.E.S.S. Collaboration has discovered a new very high energy (VHE, E > 0.1 TeV) gamma-ray source, HESS J1741-302, located in the Galactic plane. Despite several attempts to constrain its nature, no plausible counterpart has been found so far at X-ray and MeV/GeV gamma-ray energies, and the source remains unidentified. An analysis of 145-h of observations of HESS J1741-302 at VHEs has revealed a steady and relatively weak TeV source (similar to 1% of the Crab Nebula flux), with a spectral index of Gamma = 2.3 +/- 0.2(stat) +/- 0.2(sys), extending to energies up to 10 TeV without any clear signature of a cut-off. In a hadronic scenario, such a spectrum implies an object with particle acceleration up to energies of several hundred TeV. Contrary to most H.E.S.S. unidentified sources, the angular size of HESS J1741-302 is compatible with the H.E.S.S. point spread function at VHEs, with an extension constrained to be below 0.068 degrees at a 99% confidence level. The gamma-ray emission detected by H.E.S.S. can be explained both within a hadronic scenario, due to collisions of protons with energies of hundreds of TeV with dense molecular clouds, and in a leptonic scenario, as a relic pulsar wind nebula, possibly powered by the middle-aged (20 kyr) pulsar PSR B1737-30. A binary scenario, related to the compact radio source 1LC 358.266+0.038 found to be spatially coincident with the best fit position of HESS J1741-302, is also envisaged. KW - gamma rays: ISM KW - gamma rays: general KW - cosmic rays KW - ISM: clouds Y1 - 2018 U6 - https://doi.org/10.1051/0004-6361/201730581 SN - 1432-0746 VL - 612 PB - EDP Sciences CY - Les Ulis ER - TY - THES A1 - Schrön, Martin T1 - Cosmic-ray neutron sensing and its applications to soil and land surface hydrology T1 - Neutronen aus kosmischer Strahlung und deren Anwendung für Boden- und Landoberflächen-Hydrologie BT - on neutron physics, method development, and soil moisture estimation across scales N2 - Water scarcity, adaption on climate change, and risk assessment of droughts and floods are critical topics for science and society these days. Monitoring and modeling of the hydrological cycle are a prerequisite to understand and predict the consequences for weather and agriculture. As soil water storage plays a key role for partitioning of water fluxes between the atmosphere, biosphere, and lithosphere, measurement techniques are required to estimate soil moisture states from small to large scales. The method of cosmic-ray neutron sensing (CRNS) promises to close the gap between point-scale and remote-sensing observations, as its footprint was reported to be 30 ha. However, the methodology is rather young and requires highly interdisciplinary research to understand and interpret the response of neutrons to soil moisture. In this work, the signal of nine detectors has been systematically compared, and correction approaches have been revised to account for meteorological and geomagnetic variations. Neutron transport simulations have been consulted to precisely characterize the sensitive footprint area, which turned out to be 6--18 ha, highly local, and temporally dynamic. These results have been experimentally confirmed by the significant influence of water bodies and dry roads. Furthermore, mobile measurements on agricultural fields and across different land use types were able to accurately capture the various soil moisture states. It has been further demonstrated that the corresponding spatial and temporal neutron data can be beneficial for mesoscale hydrological modeling. Finally, first tests with a gyrocopter have proven the concept of airborne neutron sensing, where increased footprints are able to overcome local effects. This dissertation not only bridges the gap between scales of soil moisture measurements. It also establishes a close connection between the two worlds of observers and modelers, and further aims to combine the disciplines of particle physics, geophysics, and soil hydrology to thoroughly explore the potential and limits of the CRNS method. N2 - Wasserknappheit, Anpassung an Klimaveränderungen, und Gefahrenabschätzungen von Dürren und Fluten sind heutzutage dringende Themen für Forschung und Gesellschaft. Vorallem um die Auswirkungen auf Wetter und Landwirtschaft zu verstehen und vorherzusagen, ist es wichtig, den Wasserkreislauf der Erde zu beobachten und zu simulieren. In diesem System spielt Bodenfeuchte eine Schlüsselrolle, welche den Wasseraustausch zwischen Boden, Luft, und Pflanzen bestimmt. Daher sind ausgeklügelte Messtechnologien erforderlich, welche Bodenfeuchte von kleinen Ackerschlägen bis hin zu großen Gebieten erfassen können. Die neuartige Methode, Neutronen aus kosmischer Strahlung zu messen (CRNS), ist eine vielversprechende Technologie um die Lücke zwischen Punktmessungen und Fernerkundungen zu schließen, da der Einflussbereich des Sensors bei ca. 30 ha liegen soll. Allerdings ist intensive interdisziplinäre Forschung nötig, um die Beziehung zwischen Neutronen und Bodefeuchte zu verstehen. In dieser Arbeit wurden erstmals verschiedene Sensoren systematisch miteinander verglichen, und die bisherigen Korrekturen für meteorologische und geomagnetische Einflüsse näher untersucht. Darüber hinaus wurden Simulationen der Neutronenphysik herangezogen, um den Einflussbereich des Sensors genauestens zu charakterisieren. Demnach ist der Sensor je nach Umgebungsfeuchte hauptsächlich in der Fläche von ca. 6--18 ha, sowie besonders im Nahbereich, sensitiv. Diese Resultate konnten durch Experimente nahe Gewässern und Straßen bestätigt werden. Dennoch ist die Methode nachwievor sehr gut in der Lage, die Bodenfeuchte in Ackerflächen, Grasland und auch Wäldern zu erfassen. Zudem wurde gezeigt, dass sich die räumlichen und zeitlichen Neutronen-Daten gut für die hydrologische Modellierung eignen. Abschließend wurde eine neue Möglichkeit untersucht, um Neutronen aus der Luft mit einem Traghubschrauber in noch größeren Gebieten zu messen. Diese Dissertation untersucht die CRNS-Methode auf verschiedenen Skalen, und verknüpft dabei Beobachtung mit Modellierung. Außerdem verbindet diese Arbeit die verschiedenen Disziplinen der Teilchenphysik, Geophysik, und Bodenhydrologie, um das Potential und die Grenzen der Methode ganzheitlich zu beurteilen. KW - soil moisture KW - hydrology KW - cosmic rays KW - neutrons KW - water monitoring KW - Bodenfeuchte KW - Hydrologie KW - kosmische Strahlung KW - Neutronen KW - Wasser-Monitoring Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-395433 SN - 978-3-8439-3139-7 PB - Verlag Dr. Hut GmbH CY - München ER - TY - JOUR A1 - Abdalla, Hassan E. A1 - Aharonian, Felix A. A1 - Benkhali, F. Ait A1 - Anguener, E. O. A1 - Arakawa, M. A1 - Arcaro, C. A1 - Armand, C. A1 - Ashkar, H. A1 - Backes, M. A1 - Martins, V. Barbosa A1 - Barnard, M. A1 - Becherini, Y. A1 - Berge, D. A1 - Bernloehr, K. A1 - Blackwell, R. A1 - Boettcher, M. A1 - Boisson, C. A1 - Bolmont, J. A1 - Bonnefoy, S. A1 - Bregeon, J. A1 - Breuhaus, M. A1 - Brun, F. A1 - Brun, P. A1 - Bryan, M. A1 - Buechele, M. A1 - Bulik, T. A1 - Bylund, T. A1 - Capasso, M. A1 - Caroff, S. A1 - Carosi, A. A1 - Casanova, Sabrina A1 - Cerruti, M. A1 - Chakraborty, N. A1 - Chand, T. A1 - Chandra, S. A1 - Chaves, R. C. G. A1 - Chen, A. A1 - Colafrancesco, S. A1 - Curylo, M. A1 - Davids, I. D. A1 - Deil, C. A1 - Devin, J. A1 - de Wilt, P. A1 - Dirson, L. A1 - Djannati-Atai, A. A1 - Dmytriiev, A. A1 - Donath, A. A1 - Doroshenko, V A1 - Dyks, J. A1 - Egberts, Kathrin A1 - Emery, G. A1 - Ernenwein, J-p A1 - Eschbach, S. A1 - Feijen, K. A1 - Fegan, S. A1 - Fiasson, A. A1 - Fontaine, G. A1 - Funk, S. A1 - Fuessling, M. A1 - Gabici, S. A1 - Gallant, Y. A. A1 - Gate, F. A1 - Giavitto, G. A1 - Glawion, D. A1 - Glicenstein, J. F. A1 - Gottschall, D. A1 - Grondin, M-H A1 - Hahn, J. A1 - Haupt, M. A1 - Heinzelmann, G. A1 - Henri, G. A1 - Hermann, G. A1 - Hinton, James Anthony A1 - Hofmann, W. A1 - Hoischen, Clemens A1 - Holch, Tim Lukas A1 - Holler, M. A1 - Horns, D. A1 - Huber, D. A1 - Iwasaki, H. A1 - Jamrozy, M. A1 - Jankowsky, D. A1 - Jankowsky, F. A1 - Jung-Richardt, I A1 - Kastendieck, M. A. A1 - Katarzynski, K. A1 - Katsuragawa, M. A1 - Katz, U. A1 - Khangulyan, D. A1 - Khelifi, B. A1 - King, J. A1 - Klepser, S. A1 - Kluzniak, W. A1 - Komin, Nu A1 - Kosack, K. A1 - Kostunin, D. A1 - Kraus, M. A1 - Lamanna, G. A1 - Lau, J. A1 - Lemiere, A. A1 - Lemoine-Goumard, M. A1 - Lenain, J-P A1 - Leser, Eva A1 - Levy, C. A1 - Lohse, T. A1 - Lopez-Coto, R. A1 - Lypova, I A1 - Mackey, J. A1 - Majumdar, J. A1 - Malyshev, D. A1 - Marandon, V A1 - Marcowith, Alexandre A1 - Mares, A. A1 - Mariaud, C. A1 - Marti-Devesa, G. A1 - Marx, R. A1 - Maurin, G. A1 - Meintjes, P. J. A1 - Mitchell, A. M. W. A1 - Moderski, R. A1 - Mohamed, M. A1 - Mohrmann, L. A1 - Muller, J. A1 - Moore, C. A1 - Moulin, Emmanuel A1 - Murach, T. A1 - Nakashima, S. A1 - de Naurois, M. A1 - Ndiyavala, H. A1 - Niederwanger, F. A1 - Niemiec, J. A1 - Oakes, L. A1 - Odaka, H. A1 - Ohm, S. A1 - Wilhelmi, E. de Ona A1 - Ostrowski, M. A1 - Oya, I A1 - Panter, M. A1 - Parsons, R. D. A1 - Perennes, C. A1 - Petrucci, P-O A1 - Peyaud, B. A1 - Piel, Q. A1 - Pita, S. A1 - Poireau, V A1 - Noel, A. Priyana A1 - Prokhorov, D. A. A1 - Prokoph, H. A1 - Puehlhofer, G. A1 - Punch, M. A1 - Quirrenbach, A. A1 - Raab, S. A1 - Rauth, R. A1 - Reimer, A. A1 - Reimer, O. A1 - Remy, Q. A1 - Renaud, M. A1 - Rieger, F. A1 - Rinchiuso, L. A1 - Romoli, C. A1 - Rowell, G. A1 - Rudak, B. A1 - Ruiz-Velasco, E. A1 - Sahakian, V A1 - Saito, S. A1 - Sanchez, David M. A1 - Santangelo, A. A1 - Sasaki, M. A1 - Schlickeiser, R. A1 - Schussler, F. A1 - Schulz, A. A1 - Schutte, H. A1 - Schwanke, U. A1 - Schwemmer, S. A1 - Seglar-Arroyo, M. A1 - Senniappan, M. A1 - Seyffert, A. S. A1 - Shafi, N. A1 - Shiningayamwe, K. A1 - Simoni, R. A1 - Sinha, A. A1 - Sol, H. A1 - Specovius, A. A1 - Spir-Jacob, M. A1 - Stawarz, L. A1 - Steenkamp, R. A1 - Stegmann, Christian A1 - Steppa, Constantin Beverly A1 - Takahashi, T. A1 - Tavernier, T. A1 - Taylor, A. M. A1 - Terrier, R. A1 - Tiziani, D. A1 - Tluczykont, M. A1 - Trichard, C. A1 - Tsirou, M. A1 - Tsuji, N. A1 - Tuffs, R. A1 - Uchiyama, Y. A1 - van der Walt, D. J. A1 - van Eldik, C. A1 - van Rensburg, C. A1 - van Soelen, B. A1 - Vasileiadis, G. A1 - Veh, J. A1 - Venter, C. A1 - Vincent, P. A1 - Vink, J. A1 - Voisin, F. A1 - Voelk, H. J. A1 - Vuillaume, T. A1 - Wadiasingh, Z. A1 - Wagner, S. J. A1 - White, R. A1 - Wierzcholska, A. A1 - Yang, R. A1 - Yoneda, H. A1 - Zacharias, M. A1 - Zanin, R. A1 - Zdziarski, A. A. A1 - Zech, Alraune A1 - Ziegler, A. A1 - Zorn, J. A1 - Zywucka, N. A1 - Maxted, N. T1 - Upper limits on very-high-energy gamma-ray emission from core-collapse supernovae observed with H.E.S.S. JF - Astronomy and astrophysics : an international weekly journal N2 - Young core-collapse supernovae with dense-wind progenitors may be able to accelerate cosmic-ray hadrons beyond the knee of the cosmic-ray spectrum, and this may result in measurable gamma-ray emission. We searched for gamma-ray emission from ten super- novae observed with the High Energy Stereoscopic System (H.E.S.S.) within a year of the supernova event. Nine supernovae were observed serendipitously in the H.E.S.S. data collected between December 2003 and December 2014, with exposure times ranging from 1.4 to 53 h. In addition we observed SN 2016adj as a target of opportunity in February 2016 for 13 h. No significant gamma-ray emission has been detected for any of the objects, and upper limits on the >1 TeV gamma-ray flux of the order of similar to 10(-13) cm(-)(2)s(-1) are established, corresponding to upper limits on the luminosities in the range similar to 2 x 10(39) to similar to 1 x 10(42) erg s(-1). These values are used to place model-dependent constraints on the mass-loss rates of the progenitor stars, implying upper limits between similar to 2 x 10(-5) and similar to 2 x 10(-3) M-circle dot yr(-1) under reasonable assumptions on the particle acceleration parameters. KW - gamma rays: general KW - supernovae: general KW - cosmic rays Y1 - 2019 U6 - https://doi.org/10.1051/0004-6361/201935242 SN - 1432-0746 VL - 626 PB - EDP Sciences CY - Les Ulis ER - TY - JOUR A1 - Abdalla, Hassan E. A1 - Abramowski, A. A1 - Aharonian, Felix A. A1 - Benkhali, F. Ait A1 - Akhperjanian, A. G. A1 - Andersson, T. A1 - Anguener, E. O. A1 - Arakawa, M. A1 - Arrieta, M. A1 - Aubert, P. A1 - Backes, M. A1 - Balzer, A. A1 - Barnard, M. A1 - Becherini, Y. A1 - Tjus, J. Becker A1 - Berge, D. A1 - Bernhard, S. A1 - Bernloehr, K. A1 - Blackwell, R. A1 - Boettcher, M. A1 - Boisson, C. A1 - Bolmont, J. A1 - Bonnefoy, S. A1 - Bordas, Pol A1 - Bregeon, J. A1 - Brun, F. A1 - Brun, P. A1 - Bryan, M. A1 - Buechele, M. A1 - Bulik, T. A1 - Capasso, M. A1 - Carr, J. A1 - Casanova, Sabrina A1 - Cerruti, M. A1 - Chakraborty, N. A1 - Chaves, R. C. G. A1 - Chen, A. A1 - Chevalier, J. A1 - Coffaro, M. A1 - Colafrancesco, S. A1 - Cologna, G. A1 - Condon, B. A1 - Conrad, J. A1 - Cui, Y. A1 - Davids, I. D. A1 - Decock, J. A1 - Degrange, B. A1 - Deil, C. A1 - Devin, J. A1 - deWilt, P. A1 - Dirson, L. A1 - Djannati-Atai, A. A1 - Domainko, W. A1 - Donath, A. A1 - Dutson, K. A1 - Dyks, J. A1 - Edwards, T. A1 - Egberts, Kathrin A1 - Eger, P. A1 - Ernenwein, J. -P. A1 - Eschbach, S. A1 - Farnier, C. A1 - Fegan, S. A1 - Fernandes, M. V. A1 - Fiasson, A. A1 - Fontaine, G. A1 - Foerster, A. A1 - Funk, S. A1 - Fuessling, M. A1 - Gabici, S. A1 - Gallant, Y. A. A1 - Garrigoux, T. A1 - Giavitto, G. A1 - Giebels, B. A1 - Glicenstein, J. F. A1 - Gottschall, D. A1 - Goyal, A. A1 - Grondin, M. -H. A1 - Hahn, J. A1 - Haupt, M. A1 - Hawkes, J. A1 - Heinzelmann, G. A1 - Henri, G. A1 - Hermann, G. A1 - Hinton, J. A. A1 - Hofmann, W. A1 - Hoischen, Clemens A1 - Holch, T. L. A1 - Holler, M. A1 - Horns, D. A1 - Ivascenko, A. A1 - Iwasaki, H. A1 - Jacholkowska, A. A1 - Jamrozy, M. A1 - Janiak, M. A1 - Jankowsky, D. A1 - Jankowsky, F. A1 - Jingo, M. A1 - Jogler, T. A1 - Jouvin, L. A1 - Jung-Richardt, I. A1 - Kastendieck, M. A. A1 - Katarzynski, K. A1 - Katsuragawa, M. A1 - Katz, U. A1 - Kerszberg, D. A1 - Khangulyan, D. A1 - Khelifi, B. A1 - King, J. A1 - Klepser, S. A1 - Klochkov, D. A1 - Kluzniak, W. A1 - Kolitzus, D. A1 - Komin, Nu. A1 - Kosack, K. A1 - Krakau, S. A1 - Kraus, M. A1 - Krueger, P. P. A1 - Laffon, H. A1 - Lamanna, G. A1 - Lau, J. A1 - Lees, J. -P. A1 - Lefaucheur, J. A1 - Lefranc, V. A1 - Lemiere, A. A1 - Lemoine-Goumard, M. A1 - Lenain, J. -P. A1 - Leser, Eva A1 - Lohse, T. A1 - Lorentz, M. A1 - Liu, R. A1 - Lopez-Coto, R. A1 - Lypova, I. A1 - Marandon, V. A1 - Marcowith, Alexandre A1 - Mariaud, C. A1 - Marx, R. A1 - Maurin, G. A1 - Maxted, N. A1 - Mayer, M. A1 - Meintjes, P. J. A1 - Meyer, M. A1 - Mitchell, A. M. W. A1 - Moderski, R. A1 - Mohamed, M. A1 - Mohrmann, L. A1 - Mora, K. A1 - Moulin, Emmanuel A1 - Murach, T. A1 - Nakashima, S. A1 - de Naurois, M. A1 - Niederwanger, F. A1 - Niemiec, J. A1 - Oakes, L. A1 - Odaka, H. A1 - Ohm, S. A1 - Ostrowski, M. A1 - Oya, I. A1 - Padovani, M. A1 - Panter, M. A1 - Parsons, R. D. A1 - Pekeur, N. W. A1 - Pelletier, G. A1 - Perennes, C. A1 - Petrucci, P. -O. A1 - Peyaud, B. A1 - Piel, Q. A1 - Pita, S. A1 - Poon, H. A1 - Prokhorov, D. A1 - Prokoph, H. A1 - Puehlhofer, G. A1 - Punch, M. A1 - Quirrenbach, A. A1 - Raab, S. A1 - Rauth, R. A1 - Reimer, A. A1 - Reimer, O. A1 - Renaud, M. A1 - de los Reyes, R. A1 - Richter, S. A1 - Rieger, F. A1 - Romoli, C. A1 - Rowell, G. A1 - Rudak, B. A1 - Rulten, C. B. A1 - Sahakian, V. A1 - Saito, S. A1 - Salek, D. A1 - Sanchez, D. A. A1 - Santangelo, A. A1 - Sasaki, M. A1 - Schlickeiser, R. A1 - Schuessler, F. A1 - Schulz, A. A1 - Schwanke, U. A1 - Schwemmer, S. A1 - Seglar-Arroyo, M. A1 - Settimo, M. A1 - Seyffert, A. S. A1 - Shafi, N. A1 - Shilon, I. A1 - Simoni, R. A1 - Sol, H. A1 - Spanier, F. A1 - Spengler, G. A1 - Spies, F. A1 - Stawarz, L. A1 - Steenkamp, R. A1 - Stegmann, Christian A1 - Stycz, K. A1 - Sushch, I. A1 - Takahashi, T. A1 - Tavernet, J. -P. A1 - Tavernier, T. A1 - Taylor, A. M. A1 - Terrier, R. A1 - Tibaldo, L. A1 - Tiziani, D. A1 - Tluczykont, M. A1 - Trichard, C. A1 - Tsuji, N. A1 - Tuffs, R. A1 - Uchiyama, Y. A1 - van der Walt, D. J. A1 - van Eldik, C. A1 - van Rensburg, C. A1 - van Soelen, B. A1 - Vasileiadis, G. A1 - Veh, J. A1 - Venters, C. A1 - Viana, A. A1 - Vincent, P. A1 - Vink, J. A1 - Voisin, F. A1 - Voelk, H. J. A1 - Vuillaume, T. A1 - Wadiasingh, Z. A1 - Wagner, S. J. A1 - Wagner, P. A1 - Wagner, R. M. A1 - White, R. A1 - Wierzcholska, A. A1 - Willmann, P. A1 - Woernlein, A. A1 - Wouters, D. A1 - Yang, R. A1 - Zaborov, D. A1 - Zacharias, M. A1 - Zanin, R. A1 - Zdziarski, A. A. A1 - Zech, Alraune A1 - Zefi, F. A1 - Ziegler, A. A1 - Zywucka, N. T1 - Characterising the VHE diffuse emission in the central 200 parsecs of our Galaxy with HESS JF - Astronomy and astrophysics : an international weekly journal N2 - The diffuse very high-energy (VHE; > 100 GeV) gamma-ray emission observed in the central 200 pc of the Milky Way by H.E.S.S. was found to follow dense matter distribution in the central molecular zone (CMZ) up to a longitudinal distance of about 130 pc to the Galactic centre (GC), where the flux rapidly decreases. This was initially interpreted as the result of a burst-like injection of energetic particles 104 yr ago, but a recent more sensitive H.E.S.S. analysis revealed that the cosmic-ray (CR) density profile drops with the distance to the centre, making data compatible with a steady cosmic PeVatron at the GC. In this paper, we extend this analysis to obtain, for the first time, a detailed characterisation of the correlation with matter and to search for additional features and individual gamma-ray sources in the inner 200 pc. Taking advantage of 250 h of H.E.S.S. data and improved analysis techniques, we perform a detailed morphology study of the diffuse VHE emission observed from the GC ridge and reconstruct its total spectrum. To test the various contributions to the total gamma-ray emission, we used an iterative 2D maximum-likelihood approach that allows us to build a phenomenological model of the emission by summing a number of different spatial components. We show that the emission correlated with dense matter covers the full CMZ and that its flux is about half the total diffuse emission flux. We also detect some emission at higher latitude that is likely produced by hadronic collisions of CRs in less dense regions of the GC interstellar medium. We detect an additional emission component centred on the GC and extending over about 15 pc that is consistent with the existence of a strong CR density gradient and confirms the presence of a CR accelerator at the very centre of our Galaxy. We show that the spectrum of full ridge diffuse emission is compatible with that previously derived from the central regions, suggesting that a single population of particles fills the entire CMZ. Finally, we report the discovery of a VHE gamma-ray source near the GC radio arc and argue that it is produced by the pulsar wind nebula candidate G0.13-0.11. KW - gamma rays: general KW - gamma rays: ISM KW - Galaxy: center KW - cosmic rays Y1 - 2018 U6 - https://doi.org/10.1051/0004-6361/201730824 SN - 1432-0746 VL - 612 PB - EDP Sciences CY - Les Ulis ER - TY - THES A1 - Wieland, Volkmar T1 - Particle-in-cell simulations of perpendicular supernova shock fronts T1 - Particle-in-Cell Simulationen von senkrechten Supernova Schock-Fronten N2 - The origin of cosmic rays was the subject of several studies for over a century. The investigations done within this dissertation are one small step to shed some more light on this mystery. Locating the sources of cosmic rays is not trivial due to the interstellar magnetic field. However, the Hillas criterion allows us to arrive at the conclusion that supernova remnants are our main suspect for the origin of galactic cosmic rays. The mechanism by which they are accelerating particles is found within the field of shock physics as diffusive shock acceleration. To allow particles to enter this process also known as Fermi acceleration pre-acceleration processes like shock surfing acceleration and shock drift acceleration are necessary. Investigating the processes happening in the plasma shocks of supernova remnants is possible by utilising a simplified model which can be simulated on a computer using Particle-in-Cell simulations. We developed a new and clean setup to simulate the formation of a double shock, i.e., consisting of a forward and a reverse shock and a contact discontinuity, by the collision of two counter-streaming plasmas, in which a magnetic field can be woven into. In a previous work, we investigated the processes at unmagnetised and at magnetised parallel shocks, whereas in the current work, we move our investigation on to magnetised perpendicular shocks. Due to a much stronger confinement of the particles to the collision region the perpendicular shock develops much faster than the parallel shock. On the other hand, this leads to much weaker turbulence. We are able to find indications for shock surfing acceleration and shock drift acceleration happening at the two shocks leading to populations of pre-accelerated particles that are suitable as a seed population to be injected into further diffusive shock acceleration to be accelerated to even higher energies. We observe the development of filamentary structures in the shock ramp of the forward shock, but not at the reverse shock. This leads to the conclusion that the development of such structures in the shock ramp of quasi-perpendicular collisionless shocks might not necessarily be determined by the existence of a critical sonic Mach number but by a critical shock speed. The results of the investigations done within this dissertation might be useful for further studies of oblique shocks and for studies using hybrid or magnetohydrodynamic simulations. Together with more sophisticated observational methods, these studies will help to bring us closer to an answer as to how particles can be accelerated in supernova remnants and eventually become cosmic rays that can be detected on Earth. N2 - Der Ursprung der kosmischen Strahlung war seit über einem Jahrhundert Gegenstand von zahlreichen Untersuchungen. Die Untersuchungen, welche innerhalb dieser Dissertation gemacht wurden, sind ein kleiner Schritt dazu etwas mehr Licht auf dieses Geheimnis zu werfen. Die Quellen der kosmischen Strahlung herauszufinden stellt sich aufgrund des interstellaren Magnetfeldes als nicht trivial heraus. Jedoch erlaubt uns das Hillas-Kriterium die Schlussfolgerung, dass Supernovaüberreste unsere Hauptverdächtigen für den Ursprung der galaktischen kosmischen Strahlung sind. Der Mechanismus, durch welchen sie Teilchen beschleunigen, kann im Gebiet der Schock-Physik in Form der diffusen Schockbeschleunigung gefunden werden. Um den Teilchen zu ermöglichen an diesem Prozess, der auch als Fermi-Beschleunigung bekannt ist, teilzunehmen, sind Vorbeschleunigungsprozesse wie die Schock-Surfing-Beschleunigung und die Schock-Drift-Beschleunigung nötig. Die Untersuchung der Prozesse in Plasma-Schocks ist durch die Verwendung eines vereinfachten Modells möglich, welches sich mit Hilfe von Particle-in-Cell Simulationen auf einem Computer simulieren lässt. Wir haben einen neuen und sauberen Setup entwickelt um die Entstehung eines Doppelschocks, bestehend aus einem vorwärts und einem rückwärts gerichtet Schock und einer Kontakt-Diskontinuität, durch die Kollision zweier gegeneinander strömender Plasmen, in welche ein Magnetfeld eingelagert werden kann, zu simulieren. In einer vorhergehenden Arbeit haben wir bereits die Prozesse an unmagnetisierten und an magnetisierten parallelen Schocks untersucht, weshalb wir in der vorliegenden Arbeit zu der Untersuchung magnetisierter senkrechter Schocks weiter gegangen sind. Aufgrund eines sehr viel stärkeren Einfangens der Teilchen in der Kollisionsregion, entwickelt sich der senkrechte Schock sehr viel schneller als der parallele Schock. Andererseits führt dies zu einer viel schwächeren Turbulenz. Wir finden Anzeichen für Schock-Surfing-Beschleunigung und Schock-Drift-Beschleunigung in beiden Schocks, welche Populationen von vorbeschleunigten Teilchen erzeugen, die wiederum als Ausgangspopulation für die Injektion in die diffusive Schock-Beschleunigung geeignet sind um zu noch höheren Energien beschleunigt zu werden. Wir beobachten die Entwicklung von Filamentstrukturen in der Schockrampe des vorwärts gerichteten Schocks, jedoch nicht im rückwärts gerichtet Schock. Dies führt zu der Schlussfolgerung, dass die Entwicklung dieser Strukturen in der Schockrampe von quasi-senkrechten kollisionsfreien Schocks nicht notwendigerweise durch die Existenz einer kritischen sonischen Machzahl bestimmt ist, sondern durch eine kritische Schock-Geschwindigkeit. Die Ergebnisse der Untersuchungen in dieser Dissertation können sich für weiterführende Untersuchungen von schrägen Schocks und für Untersuchungen mit Hilfe von hybriden oder magnetohydrodynamischen Simulationen als nützlich erweisen. Zusammen mit ausgefeilteren Beobachtungsmethoden helfen uns diese Untersuchungen dabei näher an eine Antwort auf die Frage zu kommen, wie Teilchen in Supernovaüberresten beschleunigt werden können um schließlich als kosmische Strahlung auf der Erde detektiert werden zu können. KW - cosmic rays KW - kosmische Strahlung KW - supernova remnants KW - Supernovaüberreste KW - particle-in-cell simulations Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-74532 ER - TY - JOUR A1 - Acero, F. A1 - Aloisio, R. A1 - Amans, J. A1 - Amato, Elena A1 - Antonelli, L. A. A1 - Aramo, C. A1 - Armstrong, T. A1 - Arqueros, F. A1 - Asano, Katsuaki A1 - Ashley, M. A1 - Backes, M. A1 - Balazs, C. A1 - Balzer, A. A1 - Bamba, Aya A1 - Barkov, Maxim A1 - Barrio, J. A. A1 - Benbow, Wystan A1 - Bernloehr, K. A1 - Beshley, V. A1 - Bigongiari, C. A1 - Biland, A. A1 - Bilinsky, A. A1 - Bissaldi, Elisabetta A1 - Biteau, J. A1 - Blanch, O. A1 - Blasi, P. A1 - Blazek, J. A1 - Boisson, C. A1 - Bonanno, G. A1 - Bonardi, A. A1 - Bonavolonta, C. A1 - Bonnoli, G. A1 - Braiding, C. A1 - Brau-Nogue, S. A1 - Bregeon, J. A1 - Brown, A. M. A1 - Bugaev, V. A1 - Bulgarelli, A. A1 - Bulik, T. A1 - Burton, Michael A1 - Burtovoi, A. A1 - Busetto, G. A1 - Bottcher, M. A1 - Cameron, R. A1 - Capalbi, M. A1 - Caproni, Anderson A1 - Caraveo, P. A1 - Carosi, R. A1 - Cascone, E. A1 - Cerruti, M. A1 - Chaty, Sylvain A1 - Chen, A. A1 - Chen, X. A1 - Chernyakova, M. A1 - Chikawa, M. A1 - Chudoba, J. A1 - Cohen-Tanugi, J. A1 - Colafrancesco, S. A1 - Conforti, V. A1 - Contreras, J. L. A1 - Costa, A. A1 - Cotter, G. A1 - Covino, Stefano A1 - Covone, G. A1 - Cumani, P. A1 - Cusumano, G. A1 - Daniel, M. A1 - Dazzi, F. A1 - De Angelis, A. A1 - De Cesare, G. A1 - De Franco, A. A1 - De Frondat, F. A1 - Dal Pino, E. M. de Gouveia A1 - De Lisio, C. A1 - Lopez, R. de los Reyes A1 - De Lotto, B. A1 - de Naurois, M. A1 - De Palma, F. A1 - Del Santo, M. A1 - Delgado, C. A1 - della Volpe, D. A1 - Di Girolamo, T. A1 - Di Giulio, C. A1 - Di Pierro, F. A1 - Di Venere, L. A1 - Doro, M. A1 - Dournaux, J. A1 - Dumas, D. A1 - Dwarkadas, Vikram V. A1 - Diaz, C. A1 - Ebr, J. A1 - Egberts, Kathrin A1 - Einecke, S. A1 - Elsaesser, D. A1 - Eschbach, S. A1 - Falceta-Goncalves, D. A1 - Fasola, G. A1 - Fedorova, E. A1 - Fernandez-Barral, A. A1 - Ferrand, Gilles A1 - Fesquet, M. A1 - Fiandrini, E. A1 - Fiasson, A. A1 - Filipovic, Miroslav D. A1 - Fioretti, V. A1 - Font, L. A1 - Fontaine, Gilles A1 - Franco, F. J. A1 - Freixas Coromina, L. A1 - Fujita, Yutaka A1 - Fukui, Y. A1 - Funk, S. A1 - Forster, A. A1 - Gadola, A. A1 - Lopez, R. Garcia A1 - Garczarczyk, M. A1 - Giglietto, N. A1 - Giordano, F. A1 - Giuliani, A. A1 - Glicenstein, J. A1 - Gnatyk, R. A1 - Goldoni, P. A1 - Grabarczyk, T. A1 - Graciani, R. A1 - Graham, J. A1 - Grandi, P. A1 - Granot, Jonathan A1 - Green, A. J. A1 - Griffiths, S. A1 - Gunji, S. A1 - Hakobyan, H. A1 - Hara, S. A1 - Hassan, T. A1 - Hayashida, M. A1 - Heller, M. A1 - Helo, J. C. A1 - Hinton, J. A1 - Hnatyk, B. A1 - Huet, J. A1 - Huetten, M. A1 - Humensky, T. B. A1 - Hussein, M. A1 - Horandel, J. A1 - Ikeno, Y. A1 - Inada, T. A1 - Inome, Y. A1 - Inoue, S. A1 - Inoue, T. A1 - Inoue, Y. A1 - Ioka, K. A1 - Iori, Maurizio A1 - Jacquemier, J. A1 - Janecek, P. A1 - Jankowsky, D. A1 - Jung, I. A1 - Kaaret, P. A1 - Katagiri, H. A1 - Kimeswenger, S. A1 - Kimura, Shigeo S. A1 - Knodlseder, J. A1 - Koch, B. A1 - Kocot, J. A1 - Kohri, K. A1 - Komin, N. A1 - Konno, Y. A1 - Kosack, K. A1 - Koyama, S. A1 - Kraus, Michaela A1 - Kubo, Hidetoshi A1 - Mezek, G. Kukec A1 - Kushida, J. A1 - La Palombara, N. A1 - Lalik, K. A1 - Lamanna, G. A1 - Landt, H. A1 - Lapington, J. A1 - Laporte, P. A1 - Lee, S. A1 - Lees, J. A1 - Lefaucheur, J. A1 - Lenain, J. -P. A1 - Leto, Giuseppe A1 - Lindfors, E. A1 - Lohse, T. A1 - Lombardi, S. A1 - Longo, F. A1 - Lopez, M. A1 - Lucarelli, F. A1 - Luque-Escamilla, Pedro Luis A1 - Lopez-Coto, R. A1 - Maccarone, M. C. A1 - Maier, G. A1 - Malaguti, G. A1 - Mandat, D. A1 - Maneva, G. A1 - Mangano, S. A1 - Marcowith, Alexandre A1 - Marti, J. A1 - Martinez, M. A1 - Martinez, G. A1 - Masuda, S. A1 - Maurin, G. A1 - Maxted, N. A1 - Melioli, Claudio A1 - Mineo, T. A1 - Mirabal, N. A1 - Mizuno, T. A1 - Moderski, R. A1 - Mohammed, M. A1 - Montaruli, T. A1 - Moralejo, A. A1 - Mori, K. A1 - Morlino, G. A1 - Morselli, A. A1 - Moulin, Emmanuel A1 - Mukherjee, R. A1 - Mundell, C. A1 - Muraishi, H. A1 - Murase, Kohta A1 - Nagataki, Shigehiro A1 - Nagayoshi, T. A1 - Naito, T. A1 - Nakajima, D. A1 - Nakamori, T. A1 - Nemmen, R. A1 - Niemiec, Jacek A1 - Nieto, D. A1 - Nievas-Rosillo, M. A1 - Nikolajuk, M. A1 - Nishijima, K. A1 - Noda, K. A1 - Nogues, L. A1 - Nosek, D. A1 - Novosyadlyj, B. A1 - Nozaki, S. A1 - Ohira, Yutaka A1 - Ohishi, M. A1 - Ohm, S. A1 - Okumura, A. A1 - Ong, R. A. A1 - Orito, R. A1 - Orlati, A. A1 - Ostrowski, M. A1 - Oya, I. A1 - Padovani, Marco A1 - Palacio, J. A1 - Palatka, M. A1 - Paredes, Josep M. A1 - Pavy, S. A1 - Persic, M. A1 - Petrucci, P. A1 - Petruk, Oleh A1 - Pisarski, A. A1 - Pohl, Martin A1 - Porcelli, A. A1 - Prandini, E. A1 - Prast, J. A1 - Principe, G. A1 - Prouza, M. A1 - Pueschel, Elisa A1 - Puelhofer, G. A1 - Quirrenbach, A. A1 - Rameez, M. A1 - Reimer, O. A1 - Renaud, M. A1 - Ribo, M. A1 - Rico, J. A1 - Rizi, V. A1 - Rodriguez, J. A1 - Fernandez, G. Rodriguez A1 - Rodriguez Vazquez, J. J. A1 - Romano, Patrizia A1 - Romeo, G. A1 - Rosado, J. A1 - Rousselle, J. A1 - Rowell, G. A1 - Rudak, B. A1 - Sadeh, I. A1 - Safi-Harb, S. A1 - Saito, T. A1 - Sakaki, N. A1 - Sanchez, D. A1 - Sangiorgi, P. A1 - Sano, H. A1 - Santander, M. A1 - Sarkar, S. A1 - Sawada, M. A1 - Schioppa, E. J. A1 - Schoorlemmer, H. A1 - Schovanek, P. A1 - Schussler, F. A1 - Sergijenko, O. A1 - Servillat, M. A1 - Shalchi, A. A1 - Shellard, R. C. A1 - Siejkowski, H. A1 - Sillanpaa, A. A1 - Simone, D. A1 - Sliusar, V. A1 - Sol, H. A1 - Stanic, S. A1 - Starling, R. A1 - Stawarz, L. A1 - Stefanik, S. A1 - Stephan, M. A1 - Stolarczyk, T. A1 - Szanecki, M. A1 - Szepieniec, T. A1 - Tagliaferri, G. A1 - Tajima, H. A1 - Takahashi, M. A1 - Takeda, J. A1 - Tanaka, M. A1 - Tanaka, S. A1 - Tejedor, L. A. A1 - Telezhinsky, Igor O. A1 - Temnikov, P. A1 - Terada, Y. A1 - Tescaro, D. A1 - Teshima, M. A1 - Testa, V. A1 - Thoudam, S. A1 - Tokanai, F. A1 - Torres, D. F. A1 - Torresi, E. A1 - Tosti, G. A1 - Townsley, C. A1 - Travnicek, P. A1 - Trichard, C. A1 - Trifoglio, M. A1 - Tsujimoto, S. A1 - Vagelli, V. A1 - Vallania, P. A1 - Valore, L. A1 - van Driel, W. A1 - van Eldik, C. A1 - Vandenbroucke, Justin A1 - Vassiliev, V. A1 - Vecchi, M. A1 - Vercellone, Stefano A1 - Vergani, S. A1 - Vigorito, C. A1 - Vorobiov, S. A1 - Vrastil, M. A1 - Vazquez Acosta, M. L. A1 - Wagner, S. J. A1 - Wagner, R. A1 - Wakely, S. P. A1 - Walter, R. A1 - Ward, J. E. A1 - Watson, J. J. A1 - Weinstein, A. A1 - White, M. A1 - White, R. A1 - Wierzcholska, A. A1 - Wilcox, P. A1 - Williams, D. A. A1 - Wischnewski, R. A1 - Wojcik, P. A1 - Yamamoto, T. A1 - Yamamoto, H. A1 - Yamazaki, Ryo A1 - Yanagita, S. A1 - Yang, L. A1 - Yoshida, T. A1 - Yoshida, M. A1 - Yoshiike, S. A1 - Yoshikoshi, T. A1 - Zacharias, M. A1 - Zampieri, L. A1 - Zanin, R. A1 - Zavrtanik, M. A1 - Zavrtanik, D. A1 - Zdziarski, A. A1 - Zech, Alraune A1 - Zechlin, Hannes A1 - Zhdanov, V. A1 - Ziegler, A. A1 - Zorn, J. T1 - Prospects for Cherenkov Telescope Array Observations of the Young Supernova Remnant RX J1713.7-3946 JF - The astrophysical journal : an international review of spectroscopy and astronomical physics N2 - We perform simulations for future Cherenkov Telescope Array (CTA) observations of RX J1713.7-3946, a young supernova remnant (SNR) and one of the brightest sources ever discovered in very high energy (VHE) gamma rays. Special attention is paid to exploring possible spatial (anti) correlations of gamma rays with emission at other wavelengths, in particular X-rays and CO/H I emission. We present a series of simulated images of RX J1713.7-3946 for CTA based on a set of observationally motivated models for the gamma-ray emission. In these models, VHE gamma rays produced by high-energy electrons are assumed to trace the nonthermal X-ray emission observed by XMM-Newton, whereas those originating from relativistic protons delineate the local gas distributions. The local atomic and molecular gas distributions are deduced by the NANTEN team from CO and H I observations. Our primary goal is to show how one can distinguish the emission mechanism(s) of the gamma rays (i.e., hadronic versus leptonic, or a mixture of the two) through information provided by their spatial distribution, spectra, and time variation. This work is the first attempt to quantitatively evaluate the capabilities of CTA to achieve various proposed scientific goals by observing this important cosmic particle accelerator. KW - cosmic rays KW - gamma rays: ISM KW - ISM: individual objects (RX J1713.7-3946, G347.3-0.5) Y1 - 2017 U6 - https://doi.org/10.3847/1538-4357/aa6d67 SN - 0004-637X SN - 1538-4357 VL - 840 IS - 2 PB - IOP Publ. Ltd. CY - Bristol ER - TY - JOUR A1 - Abeysekara, A. U. A1 - Archer, A. A1 - Aune, Taylor A1 - Benbow, Wystan A1 - Bird, Ralph A1 - Brose, Robert A1 - Buchovecky, M. A1 - Bugaev, V. A1 - Cui, Wei A1 - Daniel, M. K. A1 - Falcone, A. A1 - Feng, Qi A1 - Finley, John P. A1 - Fleischhack, H. A1 - Flinders, A. A1 - Fortson, L. A1 - Furniss, Amy A1 - Gotthelf, Eric V. A1 - Grube, J. A1 - Hanna, David A1 - Hervet, O. A1 - Holder, J. A1 - Huang, K. A1 - Hughes, G. A1 - Humensky, T. B. A1 - Huetten, M. A1 - Johnson, Caitlin A. A1 - Kaaret, Philip A1 - Kar, P. A1 - Kelley-Hoskins, N. A1 - Kertzman, M. A1 - Kieda, David A1 - Krause, Maria A1 - Kumar, S. A1 - Lang, M. J. A1 - Lin, T. T. Y. A1 - Maier, Gernot A1 - McArthur, S. A1 - Moriarty, P. A1 - Mukherjee, Reshmi A1 - Ong, R. A. A1 - Otte, Adam Nepomuk A1 - Pandel, Dirk A1 - Park, Nahee A1 - Petrashyk, A. A1 - Pohl, Martin A1 - Popkow, Alexis A1 - Pueschel, Elisa A1 - Quinn, J. A1 - Ragan, K. A1 - Reynolds, P. T. A1 - Richards, Gregory T. A1 - Roache, E. A1 - Rousselle, J. A1 - Rulten, C. A1 - Sadeh, I. A1 - Santander, M. A1 - Sembroski, G. H. A1 - Shahinyan, Karlen A1 - Tyler, J. A1 - Vassiliev, V. V. A1 - Wakely, S. P. A1 - Ward, J. E. A1 - Weinstein, A. A1 - Wells, R. M. A1 - Wilcox, P. A1 - Wilhelm, Alina A1 - Williams, David A. A1 - Zitzer, B. T1 - A Very High Energy gamma-Ray Survey toward the Cygnus Region of the Galaxy JF - The astrophysical journal : an international review of spectroscopy and astronomical physics N2 - We present results from deep observations toward the Cygnus region using 300 hr of very high energy (VHE)gamma-ray data taken with the VERITAS Cerenkov telescope array and over 7 yr of high-energy.-ray data taken with the Fermi satellite at an energy above 1 GeV. As the brightest region of diffuse gamma-ray emission in the northern sky, the Cygnus region provides a promising area to probe the origins of cosmic rays. We report the identification of a potential Fermi-LAT counterpart to VER J2031+415 (TeV J2032+4130) and resolve the extended VHE source VER J2019+368 into two source candidates (VER J2018+367* and VER J2020+368*) and characterize their energy spectra. The Fermi-LAT morphology of 3FGL J2021.0+4031e (the Gamma Cygni supernova remnant) was examined, and a region of enhanced emission coincident with VER J2019+407 was identified and jointly fit with the VERITAS data. By modeling 3FGL J2015.6+3709 as two sources, one located at the location of the pulsar wind nebula CTB 87 and one at the quasar QSO J2015+371, a continuous spectrum from 1 GeV to 10 TeV was extracted for VER J2016+371 (CTB 87). An additional 71 locations coincident with Fermi-LAT sources and other potential objects of interest were tested for VHE gamma-ray emission, with no emission detected and upper limits on the differential flux placed at an average of 2.3% of the Crab Nebula flux. We interpret these observations in a multiwavelength context and present the most detailed gamma-ray view of the region to date. KW - acceleration of particles KW - cosmic rays KW - gamma rays: general KW - ISM: supernova remnants Y1 - 2018 U6 - https://doi.org/10.3847/1538-4357/aac4a2 SN - 0004-637X SN - 1538-4357 VL - 861 IS - 2 PB - IOP Publ. Ltd. CY - Bristol ER -