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arXiv · 1408.2891

Singlet pairing gaps of neutrons and protons in hyperonic neutron stars

Yan Xu·Cheng-Zhi Liu·Cun-Bo Fan·Xing-Wei Han·Xiao-Jun Zhang·Ming-Feng Zhu·Hong-Yan Wang·Guang-Zhou Liu
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Abstract

The $^{1}S_{0}$ nucleonic superfluids are investigated within the relativistic mean-field model and Bardeen-Cooper-Schrieffer theory in hyperonic neutron stars. The $^{1}S_{0}$ pairing gaps of neutrons and protons are calculated based on the Reid soft-core interaction as the nucleon-nucleon interaction. We have studied particularly the influence of hyperons degrees of freedom on the $^{1}S_{0}$ nucleonic pairing gap in neutron star matter. It is found that the appearance of hyperons has little impact on baryonic density range and size for the $^{1}S_{0}$ neutronic pairing gap, the $^{1}S_{0}$ protonic pairing gap also decreases slightly in this region $\rho_B=0.0-0.393$ fm$^{-3}$. However, if baryonic density becomes greater than 0.393 fm${^{-3}}$, the $^{1}S_{0}$ protonic pairing gap obviously increases. In addition, the protonic superfluid range is obviously enlarged due to the presence of hyperons. In our results, the hyperons change the $^{1}S_{0}$ protonic pairing gap which must change the cooling properties of neutron stars.

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Yan Xu, Cheng-Zhi Liu, Cun-Bo Fan, Xing-Wei Han, Xiao-Jun Zhang, Ming-Feng Zhu, Hong-Yan Wang, Guang-Zhou Liu. 2014-08-13. Singlet pairing gaps of neutrons and protons in hyperonic neutron stars. https://doi.org/10.1088/1674-4527/15/5/009

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