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Title: Dark matter and dark radiation

Abstract

We explore the feasibility and astrophysical consequences of a new long-range U(1) gauge field ('dark electromagnetism') that couples only to dark matter, not to the standard model. The dark matter consists of an equal number of positive and negative charges under the new force, but annihilations are suppressed if the dark-matter mass is sufficiently high and the dark fine-structure constant {alpha}-circumflex is sufficiently small. The correct relic abundance can be obtained if the dark matter also couples to the conventional weak interactions, and we verify that this is consistent with particle-physics constraints. The primary limit on {alpha}-circumflex comes from the demand that the dark matter be effectively collisionless in galactic dynamics, which implies {alpha}-circumflex < or approx. 10{sup -3} for TeV-scale dark matter. These values are easily compatible with constraints from structure formation and primordial nucleosynthesis. We raise the prospect of interesting new plasma effects in dark-matter dynamics, which remain to be explored.

Authors:
; ; ;  [1]
  1. California Institute of Technology, Pasadena, California 91125 (United States)
Publication Date:
OSTI Identifier:
21259792
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 79; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevD.79.023519; (c) 2009 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ANNIHILATION; ASTROPHYSICS; ELECTROMAGNETISM; FINE STRUCTURE; GAUGE INVARIANCE; MASS; NONLUMINOUS MATTER; NUCLEOSYNTHESIS; PARTICLES; PLASMA; TEV RANGE; U-1 GROUPS; WEAK INTERACTIONS

Citation Formats

Ackerman, Lotty, Buckley, Matthew R., Carroll, Sean M., and Kamionkowski, Marc. Dark matter and dark radiation. United States: N. p., 2009. Web. doi:10.1103/PHYSREVD.79.023519.
Ackerman, Lotty, Buckley, Matthew R., Carroll, Sean M., & Kamionkowski, Marc. Dark matter and dark radiation. United States. doi:10.1103/PHYSREVD.79.023519.
Ackerman, Lotty, Buckley, Matthew R., Carroll, Sean M., and Kamionkowski, Marc. 2009. "Dark matter and dark radiation". United States. doi:10.1103/PHYSREVD.79.023519.
@article{osti_21259792,
title = {Dark matter and dark radiation},
author = {Ackerman, Lotty and Buckley, Matthew R. and Carroll, Sean M. and Kamionkowski, Marc},
abstractNote = {We explore the feasibility and astrophysical consequences of a new long-range U(1) gauge field ('dark electromagnetism') that couples only to dark matter, not to the standard model. The dark matter consists of an equal number of positive and negative charges under the new force, but annihilations are suppressed if the dark-matter mass is sufficiently high and the dark fine-structure constant {alpha}-circumflex is sufficiently small. The correct relic abundance can be obtained if the dark matter also couples to the conventional weak interactions, and we verify that this is consistent with particle-physics constraints. The primary limit on {alpha}-circumflex comes from the demand that the dark matter be effectively collisionless in galactic dynamics, which implies {alpha}-circumflex < or approx. 10{sup -3} for TeV-scale dark matter. These values are easily compatible with constraints from structure formation and primordial nucleosynthesis. We raise the prospect of interesting new plasma effects in dark-matter dynamics, which remain to be explored.},
doi = {10.1103/PHYSREVD.79.023519},
journal = {Physical Review. D, Particles Fields},
number = 2,
volume = 79,
place = {United States},
year = 2009,
month = 1
}
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