Work

Symmetry energy effect on rotating neutron stars

Year: 2025

Type: article

Abstract: We explore the symmetry energy effect on the bulk properties of static neutron stars and rotating millisecond pulsars (MSPs). The unified equations of state (EOSs) are constructed self-consistently within the relativistic mean-field framework from the inner crust to the outer core. To investigate the impact of a unified EOS, which uses the same nuclear interaction for both the crust and core, we compared the results of MSPs with those obtained using non-unified EOSs. These non-unified EOSs match the crust and core EOSs, which have different slopes of symmetry energy. For a given rotational period, we examined how symmetry energy influences the maximum mass, equatorial radius, and deformation from sphericity in MSPs. Our findings indicate that a softer EOS is favored by a higher Keplerian frequency, which corresponds to a smaller L for unified EOSs, but a larger L for the crust in matching EOSs. However, under the slow rotation approximation, there is no significant effect from the symmetry energy slope on the bulk properties of 2 M ⊙ MSPs. In contrast, clear differences are observed for those around and below 1.4 M ⊙ .

Source: Astronomy and Astrophysics

DOI: 10.1051/0004-6361/202452766

Authors: Xuhao Wu, Shishao Bao, Min Ju, Jinniu Hu, Hong Shen

Institutions: Yanshan University, Shanxi Normal University, China University of Petroleum, East China, Nankai University

Language: English

Topic: Pulsars and Gravitational Waves Research

Subfield: Astronomy and Astrophysics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $1,865

Funders: National Natural Science Foundation of China, Natural Science Foundation of Hebei Province, Natural Science Foundation of Shandong Province, Fundamental Research Funds for the Central Universities