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arXiv · 2102.07099

Anisotropic compact stars: Constraining model parameters to account for physical features of tidal Love numbers

Shyam Das·Saibal Ray·Maxim Khlopov·K. K. Nandi·Bikram Keshari Parida
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Abstract

In this paper, we develop a new class of models for a compact star with anisotropic stresses inside the matter distribution. By assuming a linear equation of state for the anisotropic matter composition of the star we solve the Einstein field equations. In our approach, for the interior solutions we use a particular form of the ansatz for the metric function $g_{rr}$. The exterior solution is assumed as Schwarzschild metric and is joined with the interior metric obtained across the boundary of the star. These matching of the metrices along with the condition of the vanishing radial pressure at the boundary lead us to determine the model parameters. The physical acceptability of the solutions has verified by making use of the current estimated data available from the pulsar 4U1608-52. Thereafter, assuming anisotropy due to tidal effects we calculate the Love numbers from our model and compare the results with the observed compact stars, viz. KS 1731- 260,4U 1608- 52,4U 1724- 207,4U 1820- 30,SAX J1748.9-2021 and EXO 1745-268. The overall situation confirms physical viability of the proposed approach,which can shed new light on the interior of the compact relativistic objects.

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Shyam Das, Saibal Ray, Maxim Khlopov, K. K. Nandi, Bikram Keshari Parida. 2021-11-15. Anisotropic compact stars: Constraining model parameters to account for physical features of tidal Love numbers. https://doi.org/10.1016/j.aop.2021.168597

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