The 7 keV axion dark matter and the X-ray line signal

Abstract

We propose a scenario where the saxion dominates the energy density of the Universe and reheats the standard model sector via the dilatonic coupling, while its axionic partner contributes to dark matter decaying into photons via the same operator in supersymmetry. Interestingly, for the axion mass $m_a\simeq 7$keV and the decay constant $f_a\simeq 10^{14-15}$GeV, the recently discovered X-ray line at $3.5$keV in the XMM Newton X-ray observatory data can be explained. We discuss various cosmological aspects of the $7$keV axion dark matter such as the production of axion dark matter, the saxion decay process, hot dark matter and isocurvature constraints on the axion dark matter, and the possible baryogenesis scenarios.

20 pages, 1 figure. v2: references added

References in corpus (10)

• Four-dimensional String Compactifications with D-Branes, Orientifolds and Fluxes
• Flux Compactification
• Moduli-Induced Gravitino Problem
• Moduli Decays and Gravitinos
• Thermal axion production in the primordial quark-gluon plasma
• Moduli/Inflaton Mixing with Supersymmetry Breaking Field
• Non-thermal Production of Dark Matter from Late-Decaying Scalar Field at Intermediate Scale
• Axions and saxions from the primordial supersymmetric plasma and extra radiation signatures
• Dark radiation and small-scale structure problems with decaying particles
• Strong dynamics at the Planck scale as a solution to the cosmological moduli problem

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