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Sound in a Bubbly Hybrid Neutron Star

High Energy Physics - Phenomenology 2024-04-05 v4 High Energy Astrophysical Phenomena

Abstract

Increasingly precise astrophysical observations of the last decade in combination with intense theoretical studies allow for drawing a conclusion about potential Quark Matter presence in Neutron Stars interiors. Quark Matter may form the Neutron Star inner core or be immersed in the form of bubbles, or droplets. We consider the second scenario and demonstrate that even a small fraction of quark matter bubbles can lead to a high nonlinearity of the sound wave. Below the bubble resonant frequency the sound speed is lower than the ambient value. At the resonance it sharply grows. The peak is constrained by viscous dissipation. Above the resonance the speed exceeds the pure neutron star matter value. The dispersion equation for the bubbly neutron star compressibility is derived.

Keywords

Cite

@article{arxiv.2309.00129,
  title  = {Sound in a Bubbly Hybrid Neutron Star},
  author = {B. O. Kerbikov and M. S. Lukashov},
  journal= {arXiv preprint arXiv:2309.00129},
  year   = {2024}
}

Comments

v4: 23 pages, 3 figures; the content revised, new sections are added, some statements and typos corrected, the main statements unchanged