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Title: Oscillating asymmetric dark matter

Abstract

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

Citation Formats

Tulin, Sean, Yu, Hai-Bo, and Zurek, Kathryn M., E-mail: tulin@umich.edu, E-mail: haiboyu@umich.edu, E-mail: kzurek@umich.edu. Oscillating asymmetric dark matter. United States: N. p., 2012. Web. doi:10.1088/1475-7516/2012/05/013.
Tulin, Sean, Yu, Hai-Bo, & Zurek, Kathryn M., E-mail: tulin@umich.edu, E-mail: haiboyu@umich.edu, E-mail: kzurek@umich.edu. Oscillating asymmetric dark matter. United States. doi:10.1088/1475-7516/2012/05/013.
Tulin, Sean, Yu, Hai-Bo, and Zurek, Kathryn M., E-mail: tulin@umich.edu, E-mail: haiboyu@umich.edu, E-mail: kzurek@umich.edu. Tue . "Oscillating asymmetric dark matter". United States. doi:10.1088/1475-7516/2012/05/013.
@article{osti_22279787,
title = {Oscillating asymmetric dark matter},
author = {Tulin, Sean and Yu, Hai-Bo and Zurek, Kathryn M., E-mail: tulin@umich.edu, E-mail: haiboyu@umich.edu, E-mail: kzurek@umich.edu},
abstractNote = {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.},
doi = {10.1088/1475-7516/2012/05/013},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 05,
volume = 2012,
place = {United States},
year = {Tue May 01 00:00:00 EDT 2012},
month = {Tue May 01 00:00:00 EDT 2012}
}
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