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arXiv · 2407.12601

Prospect of unraveling the first-order phase transition in neutron stars with $f$ and $p_1$ modes

Pratik Thakur·Sagnik Chatterjee·Kamal Krishna Nath·Ritam Mallick
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Abstract

Quasi-normal modes of neutron stars are an exciting prospect for analyzing the internal composition of NSs and studying matter at high densities. In this work, we focus on studying the $f$- and $p$- quadrupolar oscillation modes, which couple with gravitational waves. We construct two different equation of state ensembles, one without and one with a first-order phase transition, and examine how $f$- and $p$-modes might help us differentiate them. We find ensemble specific exclusion regions in the $65\%$ and $95\%$ confidence contours of the frequency-damping time relations. The exclusion regions become more prominent for the higher-order oscillation modes. However, these modes have higher frequencies, which are beyond the detection capabilities of present gravitational wave detectors. The quasi-universal relations of dimensionless quantities prove to be ineffective in differentiating the equation of state ensembles, as they obscure the details of the equation of state.

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Pratik Thakur, Sagnik Chatterjee, Kamal Krishna Nath, Ritam Mallick. 2024-07-17. Prospect of unraveling the first-order phase transition in neutron stars with $f$ and $p_1$ modes. https://doi.org/10.1103/physrevd.110.103045

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