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Short-Range Correlations and Urca Process in Neutron Stars
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.
Physical Review Letters
|November 12, 2024
Summary
High-momentum neutron-proton pairs in compact stars challenge Fermi-liquid theory. Incorporating short-range correlations alters the Urca process rate, impacting theories on compact star cooling.
Area of Science:
- Nuclear Physics
- Astrophysics
- Compact Star Physics
Background:
- Recent JLab experiments reveal high-momentum neutron-proton pairs in compact stars.
- These findings deviate from predictions of the standard Fermi-liquid theory for neutron-proton fluid mixtures.
Purpose of the Study:
- To investigate the impact of non-Fermi liquid contributions on the Urca process rate in compact stars.
- To analyze how short-range correlations affect the proton spectral widths and Urca process.
Main Methods:
- Calculation of the Urca process rate.
- Inclusion of non-Fermi liquid effects from short-range correlations on proton spectral widths.
Main Results:
- The Urca process rate shows significant deviation from Fermi-liquid predictions at low temperatures.
- The previously high threshold for the Urca process in neutron stars is replaced by a smooth increase with proton fraction.
Conclusions:
- Short-range correlations significantly modify the Urca process in compact stars.
- These modifications may have substantial implications for understanding compact star cooling mechanisms.
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