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arXiv · 2305.19687

Free Energy of Anisotropic Strangeon Stars

Shichuan Chen·Yong Gao·Enping Zhou·Renxin Xu
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Abstract

Can pulsar-like compact objects release further huge free energy besides the kinematic energy of rotation? This is actually relevant to the equation of state of cold supra-nuclear matter, which is still under hot debate. Enormous energy is surely needed to understand various observations, such as $\gamma-$ray bursts, fast radio bursts and soft $\gamma-$ray repeaters. In this paper, the elastic/gravitational free energy of solid strangeon star is revisited for strangeon stars, with two anisotropic models to calculate in general relativity. It is found that huge free energy (> $10^{46}$ erg) could be released via starquakes, given an extremely small anisotropy ($(p_{\rm t}-p_{\rm r})/p_{\rm r} \sim 10^{-4}$, with $p_{\rm t}$/$p_{\rm r}$ the tangential/radial pressure), implying pulsar-like stars could have great potential of free energy release without extremely strong magnetic fields in solid strangeon star model.

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Shichuan Chen, Yong Gao, Enping Zhou, Renxin Xu. 2023-05-31. Free Energy of Anisotropic Strangeon Stars. https://doi.org/10.1088/1674-4527%2Fad1430

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