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Neutron star cooling in transiently accreting low mass binaries: a new tool for probing nuclear matter

Andrea Possenti·Monica Colpi·Dany Page·Ulrich Geppert
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Abstract

We explore, using an exact cooling code, the thermal evolution of a neutron star undergoing episodes of intense accretion, alternated by long periods of quiescence (e.g. Soft X-Ray Transients). We find that the soft component of the quiescent luminosity of Aql X-1, 4U 1608-522 and of SAX J1808.4-3658 can be understood as thermal emission from a cooling neutron star with negligible neutrino emission. In the case of Cen X-4 strong neutrino emission from the inner core is necessary to explain the observation: this may indicate that the neutron star of Cen X-4 is heavier than 1.4 Msun. This study opens the possibility of using the quiescent emission of Soft X-Ray Transients as a tool for probing the core superfluidity in relation to the mass of the neutron star.

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Andrea Possenti, Monica Colpi, Dany Page, Ulrich Geppert. 2001-02-02. Neutron star cooling in transiently accreting low mass binaries: a new tool for probing nuclear matter. https://arxiv.org/abs/astro-ph/0102047

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