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arXiv · 1905.01872

Estimating the variation of neutron star observables by symmetric dense nuclear matter properties

Péter Pósfay·Gergely Gábor Barnaföldi·Antal Jakovác
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Abstract

Recent multi-channel astrophysics observations and the soon-to-be published new measured electromagnetic and gravitation data provide information on the inner structure of the compact stars. These macroscopic observations can significantly increase our knowledge on the neutron star enteriors, providing constraints on the microscopic physical properties. On the other hand, due to the masquarade problem, there are still uncertainties on the various nuclear-matter models and their parameters as well. Calculating the properties of the dense nuclear matter, effective field theories are the most widely-used tools. However the values of the microscopical parameters need to be set consistently to the nuclear and astrophysical measurements. In this work we investigate how uncertainties are induced by the variation of the microscopical parameters. We use a symmetric nuclear matter in an extended $\sigma$-$\omega$ model. We calculate the dense matter equation of state and give the mass-radius diagram. We present that the Landau mass and compressibility modulus of the nuclear matter have definite linear relation to the maximum mass of a Schwarzschild neutron star.

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Péter Pósfay, Gergely Gábor Barnaföldi, Antal Jakovác. 2019-05-06. Estimating the variation of neutron star observables by symmetric dense nuclear matter properties. https://arxiv.org/abs/1905.01872

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