Data collected by the Pierre Auger Observatory provide evidence for anisotropy in the arrival directions of the cosmic rays with the highest-energies, which are correlated with the positions of relatively nearby active galactic nuclei (AGN) [Pierre Auger Collaboration, Science 318 (2007) 938]. The correlation has maximum significance for cosmic rays with energy greater than ∼6 × 1019 eV and AGN at a distance less than ∼75 Mpc. We have confirmed the anisotropy at a confidence level of more than 99% through a test with parameters specified a priori, using an independent data set. The observed correlation is compatible with the hypothesis that cosmic rays with the highest-energies originate from extra-galactic sources close enough so that their flux is not significantly attenuated by interaction with the cosmic background radiation (the Greisen-Zatsepin-Kuz'min effect). The angular scale of the correlation observed is a few degrees, which suggests a predominantly light composition unless the magnetic fields are very weak outside the thin disk of our galaxy. Our present data do not identify AGN as the sources of cosmic rays unambiguously, and other candidate sources which are distributed as nearby AGN are not ruled out. We discuss the prospect of unequivocal identification of individual sources of the highest-energy cosmic rays within a few years of continued operation of the Pierre Auger Observatory. © 2008 Elsevier B.V. All rights reserved.
Documento: | Artículo |
Título: | Correlation of the highest-energy cosmic rays with the positions of nearby active galactic nuclei |
Autor: | Multitudinario:447 |
Filiación: | Centro de Investigaciones en Láseres y Aplicaciones, CITEFA, CONICET, Argentina Centro Atómico Constituyentes, CNEA, Buenos Aires, Argentina Centro Atómico Constituyentes, Comisión Nacional de Energía Atómica, CONICET, Argentina Centro Atómico Constituyentes, Comisión Nacional de Energía Atómica, UTN-FRBA, Argentina Centro Atómico Bariloche, Comisión Nacional de Energía Atómica, San Carlos de Bariloche, Argentina Departamento de Física, Centro Atómico Bariloche, Comisión Nacional de Energía Atómica, Argentina Centro Atómico Bariloche, Comision Nacional de Energía Atómica, Instituto Balseiro, San Carlos de Bariloche, Argentina Departamento de Física, FCEyN, Universidad de Buenos Aires, Argentina Departamento de Física, Universidad Nacional de La Plata, Fundación Universidad Tecnológica Nacional, Argentina IFLP, Universidad Nacional de La Plata, CONICET, La Plata, Argentina Instituto de Astronomía y Física del Espacio, CONICET, Buenos Aires, Argentina Pierre Auger Southern Observatory, Malargüe, Argentina Pierre Auger Southern Observatory and Comisión Nacional de Energía Atómica, Malargüe, Argentina Universidad Tecnológica Nacional, FR-Mendoza, Argentina Universidad Tecnológica Nacional, FR-Mendoza and Fundación Universidad Tecnológica Nacional, Argentina University of Adelaide, Adelaide, SA, Australia Universidad Catolica de Bolivia, La Paz, Bolivia Universidad Mayor de San Andrés, Bolivia Centro Brasileiro de Pesquisas Fisicas, Rio de Janeiro, RJ, Brazil Pontifícia Universidade Católica, Rio de Janeiro, RJ, Brazil Universidade de Sao Paulo, Instituto de Fisica, Sao Paulo, SP, Brazil Universidade Estadual de Campinas, IFGW, Campinas, SP, Brazil Universidade Estadual de Feira de Santana, Brazil Universidade Estadual do Sudoeste da Bahia, Vitoria da Conquista, BA, Brazil Universidade Federal da Bahia, Salvador, BA, Brazil Universidade Federal, ABC, Santo André, SP, Brazil Universidade Federal do Rio de Janeiro, Instituto de Física, Rio de Janeiro, RJ, Brazil Universidade Federal Fluminense, Instituto de Fisica, Niterói, RJ, Brazil Charles University, Institute of Particle and Nuclear Physics, Prague, Czech Republic Institute of Physics, the Academy of Sciences of the Czech Republic, Prague, Czech Republic Institut de Physique Nucléaire, Université Paris-Sud, IN2P3/CNRS, Orsay, France Laboratoire AstroParticule et Cosmologie, Université Paris 7, IN2P3/CNRS, Paris, France Laboratoire de l'Accélérateur Linéaire, Université Paris-Sud, IN2P3/CNRS, Orsay, France Laboratoire de Physique Nucléaire et de Hautes Energies, Universités Paris 6 and 7, IN2P3/CNRS, Paris Cedex 05, France Laboratoire de Physique Subatomique et de Cosmologie, IN2P3/CNRS, Université Grenoble 1, Grenoble, France Bergische Universität Wuppertal, Wuppertal, Germany Forschungszentrum Karlsruhe, Institut für Kernphysik, Karlsruhe, Germany Forschungszentrum Karlsruhe, Institut für Prozessdatenverarbeitung und Elektronik, Germany Max-Planck-Institut für Radioastronomie, Bonn, Germany RWTH Aachen University, III. Physikalisches Institut A, Aachen, Germany Universität Karlsruhe, TH, Institut für Experimentelle Kernphysik, Karlsruhe, Germany Universität Siegen, Siegen, Germany Università de l'Aquila, Sezione INFN, Aquila, Italy Università di Milano, Sezione INFN, Milan, Italy Università del Salento, Sezione INFN, Lecce, Italy Università di Napoli Federico II, Sezione INFN, Napoli, Italy Università di Roma II Tor Vergata, Sezione INFN, Roma, Italy Università di Catania, Sezione INFN, Catania, Italy Università di Torino, Sezione INFN, Torino, Italy Istituto di Astrofisica Spaziale e Fisica Cosmica di Palermo, INAF, Palermo, Italy Istituto di Fisica dello Spazio Interplanetario, INAF, Università di Torino, Torino, Italy INFN, Laboratori Nazionali del Gran Sasso, Assergi, L'Aquila, Italy Osservatorio Astrofisico di Arcetri, Florence, Italy Sezione INFN di Napoli, Napoli, Italy Benemérita Universidad Autónoma de Puebla, Puebla, Mexico Centro de Investigación y de Estudios Avanzados, IPN, CINVESTAV, México, DF, Mexico Universidad Michoacana de San Nicolas de Hidalgo, Morelia, Michoacan, Mexico Universidad Nacional Autonoma de Mexico, Mexico, DF, Mexico IMAPP, Radboud University, Nijmegen, Netherlands Kernfysisch Versneller Instituut, University of Groningen, Groningen, Netherlands NIKHEF, Amsterdam, Netherlands ASTRON, Dwingeloo, Netherlands Institute of Nuclear Physics PAN, Krakow, Poland University of Łódź, Łódz, Poland LIP, Instituto Superior Técnico, Lisboa, Portugal J. Stefan Institute, Ljubljana, Slovenia Laboratory for Astroparticle Physics, University of Nova Gorica, Slovenia Instituto de Física Corpuscular, CSIC-Universitat de València, Valencia, Spain Universidad Complutense de Madrid, Madrid, Spain Universidad de Alcalá, Alcalá de Henares, Madrid, Spain Universidad de Granada, C.A.F.P.E., Granada, Spain Universidad de Santiago de Compostela, Spain Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Oxford, United Kingdom School of Physics and Astronomy, University of Leeds, United Kingdom Argonne National Laboratory, Argonne, IL, United States Case Western Reserve University, Cleveland, OH, United States Colorado School of Mines, Golden, CO, United States Colorado State University, Fort Collins, CO, United States Colorado State University, Pueblo, CO, United States Fermilab, Batavia, IL, United States Louisiana State University, Baton Rouge, LA, United States Michigan Technological University, Houghton, MI, United States New York University, New York, NY, United States Northeastern University, Boston, MA, United States Ohio State University, Columbus, OH, United States Pennsylvania State University, University Park, PA, United States Southern University, Baton Rouge, LA, United States University of California, Los Angeles, CA, United States University of Chicago, Enrico Fermi Institute, Chicago, IL, United States University of Colorado, Boulder, CO, United States University of Hawaii, Honolulu, HI, United States University of Minnesota, Minneapolis, MN, United States University of Nebraska, Lincoln, NE, United States University of New Mexico, Albuquerque, NM, United States University of Pennsylvania, Philadelphia, PA, United States University of Utah, Salt Lake City, UT, United States University of Wisconsin, Madison, WI, United States University of Wisconsin, Milwaukee, WI, United States Institute for Nuclear Science and Technology, Hanoi, Viet Nam |
Palabras clave: | AGN; Anisotropy; Auger; EGMF; Extra-galactic; GMF; GZK; High energy cosmic rays; Observatory; UHECR; Anisotropy; Galaxies; High energy physics; Magnetic field effects; Parameter estimation; Active galactic nuclei (AGN); Extra-galactic; High energy cosmic rays; Cosmic rays |
Año: | 2008 |
Volumen: | 29 |
Número: | 3 |
Página de inicio: | 188 |
Página de fin: | 204 |
DOI: | http://dx.doi.org/10.1016/j.astropartphys.2008.01.002 |
Título revista: | Astroparticle Physics |
Título revista abreviado: | Astropart. Phys. |
ISSN: | 09276505 |
CODEN: | APHYE |
Registro: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_09276505_v29_n3_p188_Multitudinario |