نوع مقاله : مقاله پژوهشی کامل
نویسندگان
دانشکده فیزیک، دانشگاه تهران، تهران، ایران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
This study investigates the effects of intense magnetic field on Equation of State (EOS) and bulk properties of neutron stars (NS). We have used a variational many-body approach to obtain the EOS of core of NS and various models are considered as basic EOS of crust of neutron stars. In this study, we focused on Landau levels of electrons. It is shown that by increasing the magnetic field, the pressure of NS is increased. Finally, the mass-radius relation of a neutron star is extracted by solving the hydrostatic equilibrium equations. It is shown that the magnetic field does not have a considerable effect on maximum mass which is obtained 2.3Mʘ by employing EOS in this study. Instead, by increasing the magnetic field inside the NS, the radius of star increases depending on the crust EOS.
کلیدواژهها [English]
[1] P. Haensel, A. Potekhin, D.G. Yakovlev. Neutron stars 1: Equation of state and structure, 326 Springer Science & Business Media, 2007. https://doi.org/10.1007/978-0-387-47301-7_3
[2] S. Tang, et al. GW170817, PSR J0030+ 0451, and PSR J0740+ 6620: constraints on phase transition and nuclear symmetry energy parameters. arXiv preprint arXiv:2106.04204 (2021). https://arxiv.org/pdf/2106.04204.pdf
[3] M. Modarres, H.R. Moshfegh, Lowest-order constrained variational calculation for β-stable matter at finite temperature. Physical Review C 62 4 (2000) 044308. https://doi.org/10.1103/PhysRevC.62.044308
[4] S. Goudarzi, H.R. Moshfegh, P. Haensel, The role of three-body forces in nuclear symmetry energy and symmetry free energy, Nuclear Physics A 969 (2018) 206-225. https://doi.org/10.1016/j.nuclphysa.2017.10.007
[5] Z.F. Gao, et al. The effects of intense magnetic fields on Landau levels in a neutron star. Astrophysics and Space Science 334 2 (2011) 281-292. https://doi.org/10.1007/s10509-011-0733-7
[6] S.L. Shapiro, S.A. Teukolsky, Black holes, white dwarfs, and neutron stars: The physics of compact objects. John Wiley & Sons, 2008. https://www.wiley.com/en-us/Black+Holes%2C+White+Dwarfs%2C+and+Neutron+Stars%3A+The+Physics+of+Compact+Objects-p-9783527617678
[7] Z. Gao, et al. Pressure of Degenerate and Relativistic electrons in a superhigh magnetic field, Modern Physics Letters A 28 36 (2013) 1350138. https://doi.org/10.1142/S0217732313501381
[8] C. Vittorio, Equation of state at ultrahigh densities. Annual Review of Astronomy and Astrophysics 13 1(1975) 335-380. https://doi.org/10.1146/annurev.aa.13.090175.002003
[9] G. Raaijmakers, et al. Constraints on the dense matter equation of state and neutron star properties from NICER's mass-radius estimate of PSR J0740+ 6620 and multimessenger observations. arXiv preprint arXiv:2105.06981 (2021). https://doi.org/10.3847/2041-8213/ac089a
[10] I. Sagert, et al. Compact stars for undergraduates. European journal of physics 27 3(2006) 577. https://doi.org/10.1088/0143-0807/27/3/012
)