Towards mitigation of apparent tension between nuclear physics and astrophysical observations by improved modeling of neutron star matter. (arXiv:2008.01582v2 [astro-ph.HE] UPDATED)

Towards mitigation of apparent tension between nuclear physics and astrophysical observations by improved modeling of neutron star matter. (arXiv:2008.01582v2 [astro-ph.HE] UPDATED)
<a href="http://arxiv.org/find/astro-ph/1/au:+Biswas_B/0/1/0/all/0/1">Bhaskar Biswas</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Char_P/0/1/0/all/0/1">Prasanta Char</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Nandi_R/0/1/0/all/0/1">Rana Nandi</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Bose_S/0/1/0/all/0/1">Sukanta Bose</a>

Observations of neutron stars (NSs) by the LIGO-Virgo and NICER
collaborations have provided reasonably precise measurements of their various
macroscopic properties. In this paper, we employ a Bayesian framework to
combine them and place improved joint constraints on the properties of NS
equation of state (EoS). We use a hybrid EoS formulation that employs a
parabolic expansion-based nuclear empirical parameterization around the nuclear
saturation density augmented by a generic 3-segment piecewise polytrope model
at higher densities. Within the $90 %$ credible level this parameterization
predicts $R_{1.4} = 12.57_{-0.92}^{+0.73}$ km and $Lambda_{1.4} =
550_{-225}^{+223}$ for the radius and dimensionless tidal deformability,
respectively, of a $1.4 M_{odot}$ NS. Finally, we show how the construction of
the full NS EoS based solely on the nuclear empirical parameters at saturation
density leads to certain tension with the astrophysical data, and how the
hybrid approach provides a resolution to it.

Observations of neutron stars (NSs) by the LIGO-Virgo and NICER
collaborations have provided reasonably precise measurements of their various
macroscopic properties. In this paper, we employ a Bayesian framework to
combine them and place improved joint constraints on the properties of NS
equation of state (EoS). We use a hybrid EoS formulation that employs a
parabolic expansion-based nuclear empirical parameterization around the nuclear
saturation density augmented by a generic 3-segment piecewise polytrope model
at higher densities. Within the $90 %$ credible level this parameterization
predicts $R_{1.4} = 12.57_{-0.92}^{+0.73}$ km and $Lambda_{1.4} =
550_{-225}^{+223}$ for the radius and dimensionless tidal deformability,
respectively, of a $1.4 M_{odot}$ NS. Finally, we show how the construction of
the full NS EoS based solely on the nuclear empirical parameters at saturation
density leads to certain tension with the astrophysical data, and how the
hybrid approach provides a resolution to it.

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