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Axion Mass Limits from Cooling Neutron Stars

Hideyuki Umeda·Naoki Iwamoto·Sachiko Tsuruta·Letao Qin·Ken'ichi Nomoto
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Abstract

The thermal evolution of a neutron star is studied by including the energy loss due to axion emission. Two axion models and three types of neutron-star matter equation of state are used with the effects of nucleon superfluidity properly taken into account. In comparison with the observational data of PSR0656+14 from ROSAT, the upper limits on the axion mass are found to be $m_a < 0.06 - 0.3$ eV and 0.08$ -$ 0.8 eV for the KSVZ and DFSZ axion models, respectively, with the soft equation of state giving the most stringent limits.

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Hideyuki Umeda, Naoki Iwamoto, Sachiko Tsuruta, Letao Qin, Ken'ichi Nomoto. 1998-06-25. Axion Mass Limits from Cooling Neutron Stars. https://arxiv.org/abs/astro-ph/9806337

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