INVESTIGADORES
MOLLERACH Maria Silvia
artículos
Título:
Anisotropy and chemical composition of ultra-high energy cosmic rays using arrival directions measured by the Pierre Auger Observatory
Autor/es:
THE PIERRE AUGER COLLABORATION, INCLUYE S. MOLLERACH
Revista:
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
Editorial:
IOP PUBLISHING LTD
Referencias:
Lugar: Londres; Año: 2011 vol. 06 p. 22 - 40
ISSN:
1475-7516
Resumen:
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.