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Title: Telescope search for decaying relic axions

Abstract

A search for optical line emission from the two-photon decay of relic axions was conducted in the galaxy clusters Abell 2667 and 2390, using spectra from the VIMOS (Visible MultiObject Spectrograph) integral field unit at the Very Large Telescope. New upper limits to the two-photon coupling of the axion are derived, and are at least a factor of 3 more stringent than previous upper limits in this mass window. The improvement follows from a larger collecting area, integration time, and spatial resolution, as well as from improvements in signal to noise and sky subtraction made possible by strong-lensing mass models of these clusters. The new limits either require that the two-photon coupling of the axion be extremely weak or that the axion mass window between 4.5 eV and 7.7 eV be closed. Implications for sterile-neutrino dark matter are discussed briefly also.

Authors:
; ;  [1];  [2];  [3];  [4]
  1. California Institute of Technology, Mail Code 130-33, Pasadena, California 91125 (United States)
  2. INAF-Osservatorio Astronomico di Capodimonte, Naples (Italy)
  3. Laboratoire d'Astrophysique de Marseilles, Traverse du Siphon, 13012 Marseilles (France)
  4. European Southern Observatory, Santiago (Chile)
Publication Date:
OSTI Identifier:
20933304
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 10; Other Information: DOI: 10.1103/PhysRevD.75.105018; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; AXIONS; EV RANGE 01-10; GALAXY CLUSTERS; MASS; NEUTRINOS; NONLUMINOUS MATTER; PARTICLE DECAY; PHOTONS; RELICT RADIATION; SIGNAL-TO-NOISE RATIO; SPATIAL RESOLUTION; TELESCOPES

Citation Formats

Grin, Daniel, Kamionkowski, Marc, Blain, Andrew, Covone, Giovanni, Kneib, Jean-Paul, and Jullo, Eric. Telescope search for decaying relic axions. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.105018.
Grin, Daniel, Kamionkowski, Marc, Blain, Andrew, Covone, Giovanni, Kneib, Jean-Paul, & Jullo, Eric. Telescope search for decaying relic axions. United States. doi:10.1103/PHYSREVD.75.105018.
Grin, Daniel, Kamionkowski, Marc, Blain, Andrew, Covone, Giovanni, Kneib, Jean-Paul, and Jullo, Eric. Tue . "Telescope search for decaying relic axions". United States. doi:10.1103/PHYSREVD.75.105018.
@article{osti_20933304,
title = {Telescope search for decaying relic axions},
author = {Grin, Daniel and Kamionkowski, Marc and Blain, Andrew and Covone, Giovanni and Kneib, Jean-Paul and Jullo, Eric},
abstractNote = {A search for optical line emission from the two-photon decay of relic axions was conducted in the galaxy clusters Abell 2667 and 2390, using spectra from the VIMOS (Visible MultiObject Spectrograph) integral field unit at the Very Large Telescope. New upper limits to the two-photon coupling of the axion are derived, and are at least a factor of 3 more stringent than previous upper limits in this mass window. The improvement follows from a larger collecting area, integration time, and spatial resolution, as well as from improvements in signal to noise and sky subtraction made possible by strong-lensing mass models of these clusters. The new limits either require that the two-photon coupling of the axion be extremely weak or that the axion mass window between 4.5 eV and 7.7 eV be closed. Implications for sterile-neutrino dark matter are discussed briefly also.},
doi = {10.1103/PHYSREVD.75.105018},
journal = {Physical Review. D, Particles Fields},
number = 10,
volume = 75,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
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