Cosmic-Ray Proton to Electron Ratios
High Energy Astrophysical Phenomena
2015-06-19 v1
Abstract
A basic quantity in the characterization of relativistic particles is the proton-to-electron (p/e) energy density ratio. We derive a simple approximate expression suitable to estimate this quantity, U_p/U_e = (m_p/m_e)^(3-q)/2, valid when a nonthermal `gas' of these particles is electrically neutral and the particles' power-law spectral indices are equal -- e.g., at injection. This relation partners the well-known p/e number density ratio at 1 GeV, i.e. N_p/N_e = (m_p/m_e)^{(q-1)/2}.
Cite
@article{arxiv.1405.3107,
title = {Cosmic-Ray Proton to Electron Ratios},
author = {M. Persic and Y. Rephaeli},
journal= {arXiv preprint arXiv:1405.3107},
year = {2015}
}
Comments
4 pages; to be published in Proc. of MGM13 (13th Marcel Grossmann Meeting -- Stockholm July 1-7, 2012)