Open Questions in Cosmic-Ray Research at Ultrahigh Energies
Abstract
We review open questions and prospects for progress in ultrahigh-energy cosmic ray (UHECR) research, based on a series of discussions that took place during the `The High-Energy Universe: Gamma-Ray, Neutrino, and Cosmic-ray Astronomy' MIAPP workshop in 2018. Specifically, we overview open questions on the origin of the bulk of UHECRs, the UHECR mass composition, the origin of the end of the cosmic-ray spectrum, the transition from Galactic to extragalactic cosmic rays, the effect of magnetic fields on the trajectories of UHECRs, anisotropy expectations for specific astrophysical scenarios, hadronic interactions, and prospects for discovering neutral particles as well as new physics at ultrahigh energies. We also briefly present upcoming and proposed UHECR experiments and discuss their projected science reach.
Keywords
Cite
@article{arxiv.1903.06714,
title = {Open Questions in Cosmic-Ray Research at Ultrahigh Energies},
author = {Rafael Alves Batista and Jonathan Biteau and Mauricio Bustamante and Klaus Dolag and Ralph Engel and Ke Fang and Karl-Heinz Kampert and Dmitriy Kostunin and Miguel Mostafa and Kohta Murase and Günter Sigl and Foteini Oikonomou and Angela V. Olinto and Mikhail I. Panasyuk and Andrew Taylor and Michael Unger},
journal= {arXiv preprint arXiv:1903.06714},
year = {2019}
}
Comments
47 pages, 17 figures, Review to appear in "Frontiers in Astronomy and Space Science" special issue, "Multi-Messenger Astrophysics: New Windows to the Universe"