Observation of a large-scale anisotropy in the arrival directions of cosmic rays above 8 × 10 18 eV

Cosmic rays are atomic nuclei arriving from outer space that reach the highest energies observed in nature. Clues to their origin come from studying the distribution of their arrival directions. Using 3 × 10 4 cosmic rays with energies above 8 × 10 18 electron volts, recorded with the Pierre Auger Observatory from a total exposure of 76,800 km2 sr year, we determined the existence of anisotropy in arrival directions. The anisotropy, detected at more than a 5.2σ level of significance, can be described by a dipole with an amplitude of 6.5 +1.3 -0.9 percent toward right ascension αd = 100 ± 10 degrees and declination δd = -24 +12 -13 degrees. That direction indicates an extragalactic origin for these ultrahighenergy particles.La nómina completa de autores puede verse en el archivo asociado a este ítem.Facultad de Ciencias Exacta

Observation of a large-scale anisotropy in the arrival directions of cosmic rays above 8 × 10 18 eV

Cosmic rays are atomic nuclei arriving from outer space that reach the highest energies observed in nature. Clues to their origin come from studying the distribution of their arrival directions. Using 3 × 10 4 cosmic rays with energies above 8 × 10 18 electron volts, recorded with the Pierre Auger Observatory from a total exposure of 76,800 km2 sr year, we determined the existence of anisotropy in arrival directions. The anisotropy, detected at more than a 5.2σ level of significance, can be described by a dipole with an amplitude of 6.5 +1.3 -0.9 percent toward right ascension αd = 100 ± 10 degrees and declination δd = -24 +12 -13 degrees. That direction indicates an extragalactic origin for these ultrahighenergy particles.La nómina completa de autores puede verse en el archivo asociado a este ítem.Facultad de Ciencias Exacta

Observation of a large-scale anisotropy in the arrival directions of cosmic rays above 8 × 10 18 eV

Cosmic rays are atomic nuclei arriving from outer space that reach the highest energies observed in nature. Clues to their origin come from studying the distribution of their arrival directions. Using 3 × 10 4 cosmic rays with energies above 8 × 10 18 electron volts, recorded with the Pierre Auger Observatory from a total exposure of 76,800 km2 sr year, we determined the existence of anisotropy in arrival directions. The anisotropy, detected at more than a 5.2σ level of significance, can be described by a dipole with an amplitude of 6.5 +1.3 -0.9 percent toward right ascension αd = 100 ± 10 degrees and declination δd = -24 +12 -13 degrees. That direction indicates an extragalactic origin for these ultrahighenergy particles.La nómina completa de autores puede verse en el archivo asociado a este ítem.Facultad de Ciencias Exacta

EuCAPT White Paper: Opportunities and Challenges for Theoretical Astroparticle Physics in the Next Decade

Astroparticle physics is undergoing a profound transformation, due to a series of extraordinary new results, such as the discovery of high-energy cosmic neutrinos with IceCube, the direct detection of gravitational waves with LIGO and Virgo, and many others. This white paper is the result of a collaborative effort that involved hundreds of theoretical astroparticle physicists and cosmologists, under the coordination of the European Consortium for Astroparticle Theory (EuCAPT). Addressed to the whole astroparticle physics community, it explores upcoming theoretical opportunities and challenges for our field of research, with particular emphasis on the possible synergies among different subfields, and the prospects for solving the most fundamental open questions with multi-messenger observations.Comment: White paper of the European Consortium for Astroparticle Theory (EuCAPT). 135 authors, 400 endorsers, 133 pages, 1382 reference