TY - CONF AU - Marsh, M. C. D. TI - Hints of a Cosmic Axion Background IS - DESY-PROC-2013-04 CY - Hamburg PB - Verlag Deutsches Elektronen-Synchrotron M1 - PUBDB-2018-02805 M1 - DESY-PROC-2013-04 SN - 978-3-935702-83-6 T2 - DESY-PROC SP - 159-163 PY - 2013 AB - In models of particle physics and cosmology arising from compactifications of string theory , the reheating of the standard model after inflation generically proceeds through the decay of heavy moduli. Non-vanishing branching ratios for moduli decay into axions generate axionic dark radiation which linger in the present universe as a homogeneous and isotropic background of relativistic axions, hence called the Cosmic Axion Background (CAB). Axion-photon conversion in magnetic fields may render the CAB visible, and we show that the soft X-ray excess observed in galaxy clusters may provide hints for the existence of a CAB. T2 - 9th Patras Workshop on Axions, WIMPs and WISPs CY - 24 Jun 2013 - 28 Jun 2013, Mainz (Germany) Y2 - 24 Jun 2013 - 28 Jun 2013 M2 - Mainz, Germany KW - Hypothetisches Teilchen (gnd) LB - PUB:(DE-HGF)29 ; PUB:(DE-HGF)8 ; PUB:(DE-HGF)7 DO - DOI:10.3204/DESY-PROC-2013-04/marsh_david UR - https://bib-pubdb1.desy.de/record/408352 ER -