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arXiv · 1304.1871

Neutron stars in a perturbative $f(R)$ gravity model with strong magnetic fields

Myung-Ki Cheoun·Cemsinan Deliduman·Can Güngör·Vildan Keleş·C. Y. Ryu·Toshitaka Kajino·Grant J. Mathews
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Abstract

We investigate the effect of a strong magnetic field on the structure of neutron stars in a model with perturbative $f(R)$ gravity. The effect of an interior strong magnetic field of about $10^{17 \sim 18}$ G on the equation of state is derived in the context of a quantum hadrodynamics (QHD) model. We solve the modified spherically symmetric hydrostatic equilibrium equations derived for a gravity model with $f(R)=R+αR^2$. Effects of both the finite magnetic field and the modified gravity are detailed for various values of the magnetic field and the perturbation parameter $α$ along with a discussion of their physical implications. We show that there exists a parameter space of the modified gravity and the magnetic field strength, in which even a soft equation of state can accommodate a large ($> 2$ M$_\odot$) maximum neutron star mass through the modified mass-radius relation.

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Myung-Ki Cheoun, Cemsinan Deliduman, Can Güngör, Vildan Keleş, C. Y. Ryu, Toshitaka Kajino, Grant J. Mathews. 2013-04-12. Neutron stars in a perturbative $f(R)$ gravity model with strong magnetic fields. https://doi.org/10.1088/1475-7516%2F2013%2F10%2F021

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