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Title: A couplet from flavored dark matter

We show that a couplet, a pair of closely spaced photon lines, in the X-ray spectrum is a distinctive feature of lepton flavored dark matter models for which the mass spectrum is dictated by Minimal Flavor Violation. In this scenario, mass splittings between different dark matter flavors are determined by Standard Model Yukawa couplings and can naturally be small, allowing all three flavors to be long-lived and contribute to the observed abundance. Then, in the presence of a tiny source of flavor violation, heavier dark matter flavors can decay via a dipole transition on cosmological timescales, giving rise to three photon lines. Two of these lines are closely spaced, and constitute the couplet. Provided the flavor violation is sufficiently small, the ratios of the line energies are determined in terms of the charged lepton masses, and constitute a prediction of this framework. Furthermore, for dark matter masses of order the weak scale, the couplet lies in the keV-MeV region, with a much weaker line in the eV-keV region. This scenario constitutes a potential explanation for the recent claim of the observation of a 3.5 keV line. As a result, the next generation of X-ray telescopes may have the necessary resolutionmore » to resolve the double line structure of such a couplet.« less
 [1] ;  [2] ;  [3] ;  [2]
  1. Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
  2. Univ. of Maryland, College Park, MD (United States)
  3. Univ. of Texas, Austin, TX (United States)
Publication Date:
Report Number(s):
FERMILAB-PUB-15-059-T; TCC-001-15; UTTG-06-15
Journal ID: ISSN 1029-8479; arXiv eprint number arXiv:1503.03057
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Journal of High Energy Physics (Online)
Additional Journal Information:
Journal Name: Journal of High Energy Physics (Online); Journal Volume: 2015; Journal Issue: 8; Journal ID: ISSN 1029-8479
Springer Berlin
Research Org:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Country of Publication:
United States
79 ASTRONOMY AND ASTROPHYSICS; beyond standard model; cosmology of theories beyond the SM; global symmetries
OSTI Identifier: