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Astrophysical bounds on supersymmetric dark-matter Q-balls

Alexander Kusenko·Lee C. Loveridge·Mikhail Shaposhnikov
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Abstract

Stable baryonic Q-balls, which appear in supersymmetric extensions of the Standard Model, could form at the end of cosmological inflation from fragmentation of the Affleck -- Dine condensate. We reconsider astrophysical constraints on such Q-balls as dark matter candidates. Baryonic Q-balls interact with matter by absorbing the baryon number and, effectively, leading to a rapid baryon number non-conservation. We have recently shown that this process can occur at a much faster rate than that used in previous calculations. As a consequence, stability of neutron stars imposes a stringent constraint on the types of Q-balls that can be dark matter. Only the Q-balls that correspond to baryonic flat directions lifted by baryon-number violating operators are allowed as dark-matter candidates.

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Alexander Kusenko, Lee C. Loveridge, Mikhail Shaposhnikov. 2005-08-04. Astrophysical bounds on supersymmetric dark-matter Q-balls. https://doi.org/10.1088/1475-7516%2F2005%2F08%2F011

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