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arXiv · 1105.3728

Unitarity constraints on asymmetric freeze-in

Anson Hook
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Abstract

This paper considers unitarity and CPT constraints on asymmetric freeze-in, the use of freeze-in to store baryon number in a dark sector. In this scenario, Sakharov's out of equilibrium condition is satisfied by placing the visible and hidden sectors at different temperatures while a net visible baryon number is produced by storing negative baryon number in a dark sector. It is shown that unitarity and CPT lead to unexpected cancellations. In particular, the transfer of baryon number cancels completely at leading order.

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Anson Hook. 2011-08-30. Unitarity constraints on asymmetric freeze-in. https://doi.org/10.1103/physrevd.84.055003

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