On UHECR origin

by Noemie Globus

at Astrophysics and Cosmology Seminar

Wed, 07 Jun 2017, 11:15
Seminar Room 207, Building 54 (Physics)

Abstract

Although their astrophysical sources remain a mystery there is a lot to learn from the study of the transition between the Galactic cosmic rays which dominate the flux up to energies around 10 18 eV and the cosmic rays of extragalactic origin at the highest energies In the past few years new measurements brought by experiments such as KASCADE Grande the Pierre Auger Observatory and Telescope Array have radically improved our knowledge of the highest energy domain of the cosmic ray spectrum In this talk I will show that the observational data across the Galactic to extragalactic cosmic ray transition up to the highest energies can be described with minimal assumptions within a generic model putting together only one Galactic component and one extragalactic component The key to the success of this model is that the protons emitted by the extragalactic sources have a different spectrum from the other types of nuclei as we recently showed to be expected in highly magn etized and photon rich environments I will finally discuss multi messenger constraints brought by neutrino and gamma ray experiments and show that our mixed composition scenario is compatible with both the most recent Fermi LAT measurements and with current IceCube limits

Created on 05-06-2017 by Bar Lev, Yevgeny (ybarlev)
Updaded on 05-06-2017 by Bar Lev, Yevgeny (ybarlev)