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arXiv · 2406.16183

Short-Range Correlations and Urca Process in Neutron Stars

Armen Sedrakian
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Abstract

Recent measurements of high-momentum correlated neutron-proton pairs at JLab suggest that the dense nucleonic component of the compact stars contains a fraction of high-momentum neutron-proton pairs that is not accounted for in the familiar Fermi-liquid theory of the neutron-proton fluid mixture. We compute the rate of the Urca process in compact stars taking into account the non-Fermi liquid contributions to the proton's spectral widths induced by short-range correlations. The Urca rate differs strongly from the Fermi-liquid prediction at low temperatures, in particular, the high threshold on the proton fraction precluding the Urca process in neutron stars is replaced by a smooth increase with the proton fraction. This observation may have a profound impact on the theories of cooling of compact stars.

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Armen Sedrakian. 2024-06-23. Short-Range Correlations and Urca Process in Neutron Stars. https://doi.org/10.1103/physrevlett.133.171401

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