Gravitational Radiation from Collapsing Magnetized Dust. II -- Polar Parity Perturbation --

TL;DR

This paper investigates how magnetic fields influence gravitational wave emission during dust star collapse, revealing magnetic effects can significantly amplify gravitational wave signals and provide insights into stellar magnetic profiles.

Contribution

It introduces a gauge-invariant perturbation approach to quantify magnetic field effects on gravitational waves in dust collapse, highlighting the potential for magnetic diagnostics.

Findings

Magnetic fields can increase gravitational wave energy emission by several orders of magnitude.

The gravitational wave output depends on initial stellar radius and magnetic field ratios.

Magnetic effects may help infer internal magnetic structures from gravitational wave observations.

Abstract

With the gauge-invariant perturbation theory, we study the effects of the stellar magnetic fields on the polar gravitational waves emitted during the homogeneous dust collapse. We found that the emitted energy in gravitational waves depends strongly not only on the initial stellar radius but also on the rasio between the poloidal and toroidal magnetic components. The polar gravitational wave output of such a collapse can be easily up to a few order of magnitude larger than what we get from the nonmagnetized collapse. The changes due to the existence of magnetic field could be helpful to extract some information of inner magnetic profiles of progenitor from the detection of the gravitational waves radiated during the black hole formation, which results from the stellar collapse.