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arXiv · 2009.05239

Impact of the neutron-star deformability on equation of state parameters

C. Y. Tsang·M. B. Tsang·Pawel Danielewicz·W. G. Lynch·F. J. Fattoyev
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Abstract

We use a Bayesian inference analysis to explore the sensitivity of Taylor expansion parameters of the nuclear equation of state (EOS) to the neutron star dimensionless tidal deformability ($Λ$) on 1 to 2 solar masses neutron stars. A global power law dependence between tidal deformability and compactness parameter (M/R) is verified over this mass region. To avoid superfluous correlations between the expansion parameters, we use a correlation-free EOS model based on a recently published meta-modeling approach. We find that assumptions in the prior distribution strongly influence the constraints on $Λ$. The $Λ$ constraints obtained from the neutron star merger event GW170817 prefer low values of $L_\text{sym}$ and $K_\text{sym}$, for a canonical neutron star with 1.4 solar mass. For neutron star with mass $<1.6$ solar mass, $L_\text{sym}$ and $K_\text{sym}$ are highly correlated with the tidal deformability. For more massive neutron stars, the tidal deformability is more strongly correlated with higher order Taylor expansion parameters.

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C. Y. Tsang, M. B. Tsang, Pawel Danielewicz, W. G. Lynch, F. J. Fattoyev. 2020-09-11. Impact of the neutron-star deformability on equation of state parameters. https://doi.org/10.1103/physrevc.102.045808

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