skip to main content

SciTech ConnectSciTech Connect

Title: Nonabelian dark matter models for 3.5 keV X-rays

A recent analysis of XXM-Newton data reveals the possible presence of an X-ray line at approximately 3.55 keV, which is not readily explained by known atomic transitions. Numerous models of eV-scale decaying dark matter have been proposed to explain this signal. Here we explore models of multicomponent nonabelian dark matter with typical mass ∼ 1-10 GeV (higher values being allowed in some models) and eV-scale splittings that arise naturally from the breaking of the nonabelian gauge symmetry. Kinetic mixing between the photon and the hidden sector gauge bosons can occur through a dimension-5 or 6 operator. Radiative decays of the excited states proceed through transition magnetic moments that appear at one loop. The decaying excited states can either be primordial or else produced by upscattering of the lighter dark matter states. These models are significantly constrained by direct dark matter searches or cosmic microwave background distortions, and are potentially testable in fixed target experiments that search for hidden photons. We note that the upscattering mechanism could be distinguished from decays in future observations if sources with different dark matter velocity dispersions seem to require different values of the scattering cross section to match the observed line strengths.
Authors:
 [1] ;  [2]
  1. Department of Physics, McGill University, 3600 rue University, Montréal, Québec, Canada H3A 2T8 (Canada)
  2. Department of Physics and Winnipeg Institute for Theoretical Physics, University of Winnipeg, Winnipeg, Manitoba, Canada R3B 2E9 (Canada)
Publication Date:
OSTI Identifier:
22375842
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2014; Journal Issue: 10; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CROSS SECTIONS; EXCITED STATES; GAUGE INVARIANCE; GEV RANGE 01-10; KEV RANGE 01-10; MAGNETIC MOMENTS; MASS; NONLUMINOUS MATTER; PHOTONS; RADIATIVE DECAY; RELICT RADIATION; SCATTERING; SIGNALS; VELOCITY; X RADIATION