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arXiv · 1205.6940

Axions from cooling compact stars: pair-breaking processes

Jochen Keller·Armen Sedrakian
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Abstract

Once formed in a supernova explosion, a neutron star cools rapidly via neutrino emission during the first 10^4-10^5 yr of its life-time. Here we compute the axion emission rate from baryonic components of a star at temperatures below their respective critical temperatures T_c for normal-superfluid phase transition. The axion production is driven by a charge neutral weak process, associated with Cooper pair breaking and recombination. The requirement that the axion cooling does not overshadow the neutrino cooling puts a lower bound on the axion decay constant f_a > 6 10^9 T_{c9}^{-1} GeV, with T_{c9} = T_c/10^9 K. This translates into a upper bound on the axion mass m_a < 10^{-3} T_{c9} eV.

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Jochen Keller, Armen Sedrakian. 2012-11-26. Axions from cooling compact stars: pair-breaking processes. https://doi.org/10.1016/j.nuclphysa.2012.11.004

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