Quasi-normal f-modes of anisotropic quark stars in full general relativity
arXiv:2504.20589 · doi:10.1103/PhysRevD.111.103035
Abstract
We investigate f-mode oscillations of anisotropic quark stars within the framework of full general relativity. We consider two different equations of state (EOSs), one is the MIT bag model EOS and the other is EOS-A. Our study examines the impact of the pressure anisotropy on the equilibrium structure, as well as on the frequencies and damping times of f-mode oscillations. Our results confirm that the f-mode frequency scales linearly with the square root of the average density, with anisotropy influencing both the slope and intercept of this relation. The dependence of the f-mode frequency on total mass reveals distinct trends based on the relative dominance of tangential and radial pressure. When the tangential pressure exceeds the radial pressure, the frequency increases with mass, exhibiting rapid growth for massive quark stars. When the radial pressure dominates, the frequency increases with mass; however, in cases where the radial pressure is significantly greater than the tangential pressure, the frequency decreases as mass increases. For low-mass quark stars, stronger tangential pressure leads to an increase in frequency, while beyond a threshold mass, a further increase in tangential pressure results in a decrease in frequency. For the chosen range of anisotropic strengths, the frequency varies between 1.3 kHz and 2.3 kHz for the MIT bag EOS and between 1.8 kHz and 3.4 kHz for EOS-A. We find that the normalized damping time follows a linear trend with compactness. For a fixed stellar mass, an increase in tangential pressure relative to radial pressure reduces the damping time, whereas a decrease in tangential pressure significantly increases it. The damping time ranges from 83 ms to 900 ms for the MIT bag EOS and from 60 ms to 761 ms for EOS-A. We present semi-empirical expressions for both the frequency and damping time as functions of mass, radius, and anisotropic strength.
arXiv commentAccepted for publication in PRD. 14 pages, 11 figures, 4 tables; abstract shortened as per arXiv constraint
References in corpus (40)
- GW170817: Observation of Gravitational Waves from a Binary Neutron Star Inspiral
- The equation of state for nucleon matter and neutron star structure
- GW190425: Observation of a Compact Binary Coalescence with Total Mass
- A unified equation of state of dense matter and neutron star structure
- Strange Quark Matter and Compact Stars
- Towards gravitational-wave asteroseismology
- Strange Stars with Realistic Quark Vector Interaction and Phenomenological Density-dependent Scalar Potential
- Gravitational waves and nonaxisymmetric oscillation modes in mergers of compact object binaries
- Non-radial oscillations of anisotropic neutron stars in the Cowling approximation
- Exploring properties of high-density matter through remnants of neutron-star mergers
- Radial pulsations and stability of anisotropic stars with quasi-local equation of state
- Density Discontinuity of a Neutron Star and Gravitational Waves
- Quasi-Normal Modes of General Relativistic Superfluid Neutron Stars
- Non-radial oscillation modes as a probe of density discontinuities in neutron stars
- Relativistic models of magnetars: Nonperturbative analytical approach
- Nonradial oscillations of quark stars
- A light strange star in the remnant HESS J1731-347: minimal consistency checks
- Anisotropic neutron stars in gravity
- Phase Transition and Anisotropic Deformations of Neutron Star Matter
- Is PSR B0943+10 a low-mass quark star?
- Accuracy of relativistic Cowling approximation in protoneutron star asteroseismology
- Frequency deviations in universal relations of isolated neutron stars and postmerger remnants
- The Cooling Neutron Star in 3C 58
- The evolution of the f-mode instability in neutron stars and gravitational wave detectability
- The crust of rotating strange quark stars
- Quark matter imprint on Gravitational Waves from oscillating stars
- Compact strange stars with a medium dependence in gluons at finite temperature
- Exploring universality in neutron star mergers
- -mode Imprints in Gravitational Waves from Coalescing Binaries involving Aligned Spinning Neutron Stars
- Recycling strange stars to millisecond periods
- Non-radial oscillations in newly born compact star considering effects of phase transition
- Discrimination of Quark Stars from Neutron Stars in Quadrupole Oscillations
- Recent progresses in strange quark stars
- The stochastic background of gravitational waves due to the f-mode instability in neutron stars
- A model finding a new Richardson potential with different scales for confinement and asymptotic freedom, by fitting the properties of ${\D}^{++}$ and ${\Om}^{-}$
- Universal relations for anisotropic interacting quark stars
- f-mode oscillations of anisotropic neutron stars in full general relativity
- Gravitational waves from glitch-induced f-mode oscillations in quark and neutron stars
- Gravitational waves from nonradial oscillations of stochastically accreting neutron stars
- Mean field baryon magnetic moments and sumrules