English

Quasi-normal g-modes of neutron stars with quarks

General Relativity and Quantum Cosmology 2022-06-08 v1 High Energy Astrophysical Phenomena Solar and Stellar Astrophysics Nuclear Theory

Abstract

Quasi-normal oscillation modes of neutron stars provide a means to probe their interior composition using gravitational wave astronomy. We compute the frequencies and damping times of composition-dependent core g-modes of neutron stars containing quark matter employing linearized perturbative equations of general relativity. We find that ignoring background metric perturbations due to the oscillating fluid, as in the Cowling approximation, underestimates the g-mode frequency by up to 10% for higher mass stars, depending on the parameters of the nuclear equation of state and how the mixed phase is constructed. The g-mode frequencies are well-described by a linear scaling with the central lepton (or combined lepton and quark) fraction for nucleonic (hybrid) stars. Our findings suggest that neutron stars with and without quarks are manifestly different with regards to their quasi-normal g-mode spectrum, and may thus be distinguished from one another in future observations of gravitational waves from merging neutron stars.

Keywords

Cite

@article{arxiv.2202.01403,
  title  = {Quasi-normal g-modes of neutron stars with quarks},
  author = {Tianqi Zhao and Constantinos Constantinou and Prashanth Jaikumar and Madappa Prakash},
  journal= {arXiv preprint arXiv:2202.01403},
  year   = {2022}
}

Comments

14 pages, 10 figures