Mixed axion/neutralino dark matter in the SUSY DFSZ axion model

Journal Article · Sun Dec 01 04:00:00 EST 2013 · Journal of Cosmology and Astroparticle Physics

DOI:https://doi.org/10.1088/1475-7516/2013/12/028· OSTI ID:22369860

Bae, Kyu Jung; Baer, Howard ^[1]

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1. Department of Physics and Astronomy, University of Oklahoma, Norman, OK 73019 (United States)

We examine mixed axion/neutralino cold dark matter production in the SUSY DFSZ axion model where an axion superfield couples to Higgs superfields. We calculate a wide array of axino and saxion decay modes along with their decay temperatures, and thermal and non-thermal production rates. For a SUSY benchmark model with a standard underabundance (SUA) of Higgsino-like dark matter (DM), we find for the PQ scale f{sub a}∼<10{sup 12} GeV that the DM abundance is mainly comprised of axions as the saxion/axino decay occurs before the standard neutralino freeze-out and thus its abundance remains suppressed. For 10{sup 12}∼10{sup 14} GeV, both neutralino dark matter and dark radiation are typically overproduced. For judicious parameter choices, these can be suppressed and the combined neutralino/axion abundance brought into accord with measured values. A SUSY benchmark model with a standard overabundance (SOA) of bino DM is also examined and typically remains excluded due at least to too great a neutralino DM abundance for f{sub a}∼<10{sup 15} GeV. For f{sub a}∼>10{sup 15} GeV and lower saxion masses, large entropy production from saxion decay can dilute all relics and the SOA model can be allowed by all constraints.

• OSTI ID: 22369860
• Journal Information: Journal of Cosmology and Astroparticle Physics, Journal Name: Journal of Cosmology and Astroparticle Physics Journal Issue: 12 Vol. 2013; ISSN 1475-7516
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ANNIHILATION
AXIONS
ENTROPY
GEV RANGE
HIGGS BOSONS
HIGGS MODEL
MASS
NONLUMINOUS MATTER
PARTICLE DECAY
SUPERSYMMETRY