Decoupling of superfluid and normal modes in pulsating neutron stars

Abstract

We show that equations governing pulsations of superfluid neutron stars can be splitted into two sets of weakly coupled equations, one describing the superfluid modes and another one -- the normal modes. The coupling parameter s is small, |s| ~ 0.01-0.05, for realistic equations of state. Already an approximation s=0 is sufficient to calculate the pulsation spectrum within the accuracy of a few percents. Our results indicate, in particular, that emission of gravitational waves from superfluid pulsation modes is suppressed in comparison to that from normal modes. The proposed approach allows to drastically simplify modeling of pulsations of superfluid neutron stars.

5 pages, 2 figures; published version + mistake in Eq.(6) and a few typos are corrected; results unchanged

References in corpus (8)

• Shapiro delay measurement of a two solar mass neutron star
• Neutron Star Observations: Prognosis for Equation of State Constraints
• Gravitational waves from neutron stars: Promises and challenges
• Bulk viscosity of superfluid neutron stars
• Oscillations of General Relativistic Multi-fluid/Multi-layer Compact Stars
• Temperature-dependent pulsations of superfluid neutron stars
• The relativistic entrainment matrix of a superfluid nucleon-hyperon mixture at zero temperature
• The relativistic entrainment matrix of a superfluid nucleon-hyperon mixture. II. Effect of finite temperatures

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• Quasi-normal modes of superfluid neutron stars
• Dissipation in relativistic superfluid neutron stars
• Temperature-dependent r-modes in superfluid neutron stars stratified by muons
• Dynamical tides in superfluid neutron stars
• Nonradial superfluid modes in oscillating neutron stars
• Compressional modes in two-superfluid neutron stars with leptonic buoyancy
• $g$-mode of neutron stars in pseudo-Newtonian gravity