Delineating effects of nuclear symmetry energy on the radii and tidal polarizabilities of neutron stars

Journal Article · 26 November 2018 · Journal of Physics. G, Nuclear and Particle Physics

DOI: https://doi.org/10.1088/1361-6471/aaef54 · OSTI ID:1658237

Zhang, Nai-Bo ^[1]; Li, Bao-An  ^[2]

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1. Shandong Univ., Weihai (China); Texas A & M Univ., Commerce, TX (United States); Texas A&M University-Commerce
2. Texas A & M Univ., Commerce, TX (United States)

Here, what can we learn about the density dependence of nuclear symmetry energy $${E}_{\mathrm{sym}}(\rho)$$ from precise measurements of the radius (R_1.4) and/or tidal polarizability (Λ_1.4) of canonical neutron stars with a mass of 1.4 $${{\rm{M}}}_{\odot }$$? With the $${E}_{\mathrm{sym}}(\rho)$$ parameterized using three parameters L, K_sym, and J_sym which have the asymptotic meaning of being respectively the slope, curvature, and skewness of symmetry energy at saturation density, we found that, while both the R_1.4 and Λ_1.4 depend strongly on the slope L, the K_sym and J_sym parameters characterizing the high-density behavior of $${E}_{\mathrm{sym}}(\rho)$$ also play appreciable roles. Thus, there is not a simple relation between the Λ_1.4/R_1.4 and L alone. Precise measurements of just the Λ_1.4 and R_1.4 cannot completely determine the $${E}_{\mathrm{sym}}(\rho)$$ but limit combinations of its parameters. In particular, stringent constraints approximately independent of the J_sym on the L–K_sym correlations can be obtained. However, infinite combinations of the larger (smaller) L and smaller (larger) K_sym can lead to the same Λ_1.4 and R_1.4. Additional observables including those from terrestrial nuclear experiments are thus necessary to break this degeneracy in order to completely determine the density dependence of nuclear symmetry energy $${E}_{\mathrm{sym}}(\rho)$$.

• Research Organization: Texas A & M Univ., Commerce, TX (United States)
• Sponsoring Organization: National Natural Science Foundation of China (NNSFC); USDOE Office of Science (SC), Nuclear Physics (NP)
• Grant/Contract Number: SC0009971; SC0013702
• OSTI ID: 1658237
• Journal Information: Journal of Physics. G, Nuclear and Particle Physics, Journal Name: Journal of Physics. G, Nuclear and Particle Physics Journal Issue: 1 Vol. 46; ISSN 0954-3899
• Publisher: IOP PublishingCopyright Statement
• Country of Publication: United States
• Language: English