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arXiv · 2203.16827

Pasta properties of the neutron star within effective relativistic mean-field model

Abstract

We study the properties of pasta structures and their influence on the neutron star observables employing the effective relativistic mean-field (E-RMF) model. The compressible liquid drop model is used to incorporate the finite size effects, considering the possibility of nonspherical structures in the inner crust. The unified equation of states are constructed for several E-RMF parameters to study various properties such as pasta mass and thickness in the neutron star's crust. The majority of the pasta properties are sensitive to the symmetry energy in the subsaturation density region. Using the results from Monte Carlo simulations, we estimate the shear modulus of the crust in the context of quasiperiodic oscillations from soft gamma-ray repeaters and calculate the frequency of fundamental torsional oscillation mode in the inner crust. Global properties of the neutron star such as mass-radius profile, the moment of inertia, crustal mass, crustal thickness, and fractional crustal moment of inertia are worked out. The results are consistent with various observational and theoretical constraints.

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Vishal Parmar, H. C. Das, Ankit Kumar, M. K. Sharma, P. Arumugam, S. K. Patra. 2022-07-29. Pasta properties of the neutron star within effective relativistic mean-field model. https://doi.org/10.1103/physrevd.106.023031

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