Cosmic infrared background excess from axionlike particles and implications for multimessenger observations of blazars
Oleg E. Kalashev (Institute for Nuclear Research, 60th October Anniversary Prospect 7a, Moscow 117312 Russia, Moscow Institute for Physics and Technology, 9 Institutskiy per., Dolgoprudny, Moscow Region, 141701 Russia); Alexander Kusenko (Department of Physics and Astronomy, University of California, Los Angeles, California 90095-1547, USA, Kavli IPMU (WPI), University of Tokyo, Kashiwa, Chiba 277-8 568, Japan); Edoardo Vitagliano (Max-Planck-Institut für Physik (Werner-Heisenberg-Institut), Föhringer Ring 6, 80805 München, Germany)
The first measurement of the diffuse background spectrum at from the CIBER experiment has revealed a significant excess of the cosmic infrared background (CIB) radiation compared to the theoretically expected spectrum. We revisit the hypothesis that decays of axionlike particle (ALP) can explain this excess, extending previous analyses to the case of a warm relic population. We show that such a scenario is not excluded by anisotropy measurements nor by stellar cooling arguments. Moreover, we find that the increased extragalactic background light (EBL) does not contradict observations of blazar spectra. Furthermore, the increased EBL attenuates the diffuse TeV gamma-ray flux and alleviates the tension between the detected neutrino and gamma ray fluxes.
