Journal of High Energy Physics

, 2014:140 | Cite as

Displaced vertices from X-ray lines

  • Adam Falkowski
  • Yonit Hochberg
  • Joshua T. Ruderman
Open Access
Regular Article - Theoretical Physics


We present a simple model of weak-scale thermal dark matter that gives rise to X-ray lines. Dark matter consists of two nearly degenerate states near the weak scale, which are populated thermally in the early universe via co-annihilation with slightly heavier states that are charged under the Standard Model. The X-ray line arises from the decay of the heavier dark matter component into the lighter one via a radiative dipole transition, at a rate that is slow compared to the age of the universe. The model predicts observable signatures at the LHC in the form of exotic events with missing energy and displaced leptons and jets. As an application, we show how this model can explain the recently observed 3.55 keV X-ray line.


Beyond Standard Model Cosmology of Theories beyond the SM 


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Copyright information

© SISSA, Trieste, Italy 2014

Authors and Affiliations

  • Adam Falkowski
    • 1
  • Yonit Hochberg
    • 2
    • 3
  • Joshua T. Ruderman
    • 4
  1. 1.Laboratoire de Physique Théorique, CNRS — UMR 8627, Université de Paris-Sud 11Orsay CedexFrance
  2. 2.Ernest Orlando Lawrence Berkeley National LaboratoryUniversity of CaliforniaBerkeleyU.S.A.
  3. 3.Department of PhysicsUniversity of CaliforniaBerkeleyU.S.A.
  4. 4.Center for Cosmology and Particle Physics, Department of PhysicsNew York UniversityNew YorkU.S.A.

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