Composition temperature-dependent g-modes in superfluid neutron stars

TL;DR

This paper explores temperature-dependent composition g-modes in superfluid neutron stars, calculating their frequencies and showing they can be quite high, challenging the use of barotropic equations of state for inertial mode analysis.

Contribution

It introduces the concept of temperature-dependent composition g-modes in superfluid neutron stars and calculates their eigenfrequencies, revealing their significance in neutron star oscillation modeling.

Findings

g-modes have eigenfrequencies up to ~500 Hz

Barotropic equations of state may be inadequate for inertial modes

Temperature influences the existence of composition g-modes

Abstract

We demonstrate a possibility of existence of a peculiar temperature-dependent composition $g$-modes in superfluid neutron stars. We calculate the Brunt-V$\ddot{\rm a}$is$\ddot{\rm a}$l$\ddot{\rm a}$ frequency for these modes, as well as their eigenfrequencies. The latter turn out to be rather large, up to $\sim 500$ Hz for a chosen model of a neutron star. This result indicates, in particular, that use of the barotropic equation of state may be not a good approximation for calculation of inertial modes even in most rapidly rotating superfluid neutron stars.