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Title: Oscillating asymmetric dark matter

We study the dynamics of dark matter (DM) particle-antiparticle oscillations within the context of asymmetric DM. Oscillations arise due to small DM number-violating Majorana-type mass terms, and can lead to recoupling of annihilation after freeze-out and washout of the DM density. Asymmetric DM oscillations 'interpolate' between symmetric and asymmetric DM freeze-out scenarios, and allow for a larger DM model-building parameter space. We derive the density matrix equations for DM oscillations and freeze-out from first principles using nonequilibrium field theory, and our results are qualitatively different than in previous studies. DM dynamics exhibits particle-vs-antiparticle 'flavor' effects, depending on the interaction type, analogous to neutrino oscillations in a medium. 'Flavor-sensitive' DM interactions include scattering or annihilation through a new vector boson, while 'flavor-blind' interactions include scattering or s-channel annihilation through a new scalar boson. In particular, we find that flavor-sensitive annihilation does not recouple when coherent oscillations begin, and that flavor-blind scattering does not lead to decoherence.
Authors:
; ;  [1]
  1. Michigan Center for Theoretical Physics, Department of Physics, University of Michigan, Ann Arbor, MI, 48109 (United States)
Publication Date:
OSTI Identifier:
22279787
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2012; Journal Issue: 05; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ANNIHILATION; ANTIPARTICLES; ASTROPHYSICS; ASYMMETRY; BOSONS; COSMOLOGY; DENSITY MATRIX; FIELD THEORIES; FLAVOR MODEL; NEUTRINO OSCILLATION; NONLUMINOUS MATTER; S CHANNEL; SCALARS; SCATTERING; SYMMETRY