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Title: Axions and high-energy cosmic rays: can the relic axion density be measured?

Abstract

In a previous work we investigated the propagation of fast moving charged particles in a spatially constant but slowly time dependent pseudoscalar background, such as the one provided by cold relic axions. The background induces cosmic rays to radiate in the low-energy spectrum. While the energy loss caused by this mechanism on the primary cosmic rays is negligible, we investigate the hypothetical detection of the photons radiated and how they could provide an indirect way of verifying the cosmological relevance of axions. Assuming that the cosmic ray flux is of the form J(E) ∼ E{sup −γ} we find that the energy radiated via this mechanism has a power spectrum k to the power of minus gamma minus 1 over 2 for proton primaries and k to the power of minus gamma over 2 for electron primaries, which dominate for low values of k where the effect is maximized. Unfortunately this radiation is shadowed by the synchrotron radiation background making the observation of this effect very difficult. Yet its detection would constitute direct evidence of the presence of a cold axion background.

Authors:
 [1]; ;  [2]
  1. CERN, 1211 Geneva (Switzerland)
  2. Departament d'Estructura i Constituents de la Matèria and Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona, Martí i Franquès 1, 08028 Barcelona (Spain)
Publication Date:
OSTI Identifier:
22277796
Resource Type:
Journal Article
Journal Name:
Journal of Cosmology and Astroparticle Physics
Additional Journal Information:
Journal Volume: 2011; Journal Issue: 08; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1475-7516
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASTROPHYSICS; AXIONS; CHARGED PARTICLES; COSMIC RAY FLUX; COSMIC RAY PROPAGATION; COSMOLOGY; ELECTRONS; ENERGY LOSSES; ENERGY SPECTRA; PHOTONS; PRIMARY COSMIC RADIATION; PROTONS; SYNCHROTRON RADIATION; TIME DEPENDENCE

Citation Formats

Espriu, D., Mescia, F., and Renau, A., E-mail: espriu@ecm.ub.es, E-mail: mescia@ub.edu, E-mail: arencer@gmail.com. Axions and high-energy cosmic rays: can the relic axion density be measured?. United States: N. p., 2011. Web. doi:10.1088/1475-7516/2011/08/002.
Espriu, D., Mescia, F., & Renau, A., E-mail: espriu@ecm.ub.es, E-mail: mescia@ub.edu, E-mail: arencer@gmail.com. Axions and high-energy cosmic rays: can the relic axion density be measured?. United States. doi:10.1088/1475-7516/2011/08/002.
Espriu, D., Mescia, F., and Renau, A., E-mail: espriu@ecm.ub.es, E-mail: mescia@ub.edu, E-mail: arencer@gmail.com. Mon . "Axions and high-energy cosmic rays: can the relic axion density be measured?". United States. doi:10.1088/1475-7516/2011/08/002.
@article{osti_22277796,
title = {Axions and high-energy cosmic rays: can the relic axion density be measured?},
author = {Espriu, D. and Mescia, F. and Renau, A., E-mail: espriu@ecm.ub.es, E-mail: mescia@ub.edu, E-mail: arencer@gmail.com},
abstractNote = {In a previous work we investigated the propagation of fast moving charged particles in a spatially constant but slowly time dependent pseudoscalar background, such as the one provided by cold relic axions. The background induces cosmic rays to radiate in the low-energy spectrum. While the energy loss caused by this mechanism on the primary cosmic rays is negligible, we investigate the hypothetical detection of the photons radiated and how they could provide an indirect way of verifying the cosmological relevance of axions. Assuming that the cosmic ray flux is of the form J(E) ∼ E{sup −γ} we find that the energy radiated via this mechanism has a power spectrum k to the power of minus gamma minus 1 over 2 for proton primaries and k to the power of minus gamma over 2 for electron primaries, which dominate for low values of k where the effect is maximized. Unfortunately this radiation is shadowed by the synchrotron radiation background making the observation of this effect very difficult. Yet its detection would constitute direct evidence of the presence of a cold axion background.},
doi = {10.1088/1475-7516/2011/08/002},
journal = {Journal of Cosmology and Astroparticle Physics},
issn = {1475-7516},
number = 08,
volume = 2011,
place = {United States},
year = {2011},
month = {8}
}