Anisotropy and chemical composition of ultra-high energy cosmic rays using arrival directions measured by the Pierre Auger Observatory

0371933 - FZÚ 2013 RIV GB eng J - Journal Article
Abreu, P. - Aglietta, M. - Ahn, E.J. - Boháčová, Martina - Chudoba, Jiří - Ebr, Jan - Mandát, Dušan - Nečesal, Petr - Nožka, Libor - Nyklíček, Michal - Palatka, Miroslav - Pech, Miroslav - Prouza, Michael - Řídký, Jan - Schovancová, Jaroslava - Schovánek, Petr - Šmída, Radomír - Trávníček, Petr - Vícha, Jakub … Total 493 authors
Anisotropy and chemical composition of ultra-high energy cosmic rays using arrival directions measured by the Pierre Auger Observatory.
Journal of Cosmology and Astroparticle Physics. Roč. 11, č. 6 (2011), 1-15. ISSN 1475-7516. E-ISSN 1475-7516
R&D Projects: GA MŠMT LC527; GA MŠMT(CZ) 1M06002; GA MŠMT(CZ) MEB111003; GA AV ČR KJB100100904; GA AV ČR KJB300100801
Institutional research plan: CEZ:AV0Z10100502; CEZ:AV0Z10100522
Keywords : ultra high energy cosmic rays * cosmic ray experiments
Subject RIV: BF - Elementary Particles and High Energy Physics
Impact factor: 5.723, year: 2011
http://iopscience.iop.org/1475-7516/2011/06/022/pdf/1475-7516_2011_06_022.pdf

The Pierre Auger Collaboration has reported evidence for anisotropy in the distribution of arrival directions of the cosmic rays with energies E > Eth = 5.5×1019 eV. These show a correlation with the distribution of nearby extragalactic objects, including an apparent excess around the direction of Centaurus A. If the particles responsible for these excesses at E > Eth are heavy nuclei with charge Z, the proton component of the sources should lead to excesses in the same regions at energies E/Z. We here report the lack of anisotropies in these directions at energies above Eth/Z (for illustrative values of Z = 6, 13, 26). If the anisotropies above Eth are due to nuclei with charge Z, and under reasonable assumptions about the acceleration process, these observations imply stringent constraints on the allowed proton fraction at the lower energies.
Permanent Link: http://hdl.handle.net/11104/0205340