Resonant growth of stellar oscillations by incident gravitational waves

TL;DR

This paper investigates how incident gravitational waves can resonantly amplify stellar oscillations, demonstrating that certain conditions involving wave amplitude, frequency, and damping time lead to significant growth.

Contribution

It introduces a simple toy model showing the conditions under which gravitational waves can resonantly grow stellar oscillations, including the role of radiation damping.

Findings

Resonant growth occurs when the product of wave amplitude, frequency, and damping time exceeds a threshold.

The model predicts specific resonance modes where growth is most significant.

Oscillation growth depends critically on the interplay of incident wave parameters and stellar damping.

Abstract

Stellar oscillation under the combined influences of incident gravitational wave and radiation loss is studied in a simple toy model. The star is approximated as a uniform density ellipsoid in the Newtonian gravity including radiation damping through quadrupole formula. The time evolution of the oscillation is significantly controlled by the incident wave amplitude $h$, frequency $\nu$ and damping time $\tau$. If a combination $ h \nu \tau $ exceeds a threshold value, which depends on the resonance mode, the resonant growth is realized.