Short-Range Correlations and Urca Process in Neutron Stars
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Updated: Jun 7, 2025

High-Resolution Neutron Spectroscopy to Study Picosecond-Nanosecond Dynamics of Proteins and Hydration Water
Published on: April 28, 2022
1<a href="https://ror.org/05vmv8m79">Frankfurt Institute for Advanced Studies</a>, D-60438 Frankfurt am Main, Germany and Institute of Theoretical Physics, <a href="https://ror.org/00yae6e25">University of Wroclaw</a>, 50-204 Wroclaw, Poland.
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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