Transition from Galactic to Extragalactic Cosmic Rays
Journal article, Peer reviewed
Published version
View/ Open
Date
2019Metadata
Show full item recordCollections
- Institutt for fysikk [2652]
- Publikasjoner fra CRIStin - NTNU [37215]
Original version
The European Physical Journal Conferences. 2019, 210 . 10.1051/epjconf/201921004003Abstract
The question at which energy the transition from Galactic to extragalactic cosmic rays takes place has been a long-standing conundrum in cosmic ray physics. In the past, the transition energy has been usually associated with one of the evident features of the cosmic ray spectrum: The second knee around E≃5 ×1017 eV or the ankle at E≃3 ×1018 eV. I review anisotropy and composition data and show that they require that the transition from Galacticto extragalactic CRs has to happen early, at few ×1017 eV. As a result, a successful model for the transition should explain the ankle as a feature of the extragalactic CR spectrum. I review briefly such models and their implications.