Gravitational waves from gaps of neutron stars

TL;DR

This paper estimates gravitational wave strain from neutron star magnetospheres, finding the outer gap could produce detectable signals for future observatories, offering a new way to probe magnetospheric physics.

Contribution

It introduces a novel approach to estimate gravitational wave strain from neutron star gaps, highlighting the outer gap as a promising detection source.

Findings

Strain from the polar cap is too small for detection.

Outer gap strain can reach ~2×10⁻²⁴, detectable by future detectors.

Proposes a new method to probe magnetosphere physics via gravitational waves.

Abstract

The pulsar magnetosphere is a potential source of continuous gravitational waves due to the rapid charge-discharge process in short timescale, varying the electric-field energy density. We estimate the strain of the continuous gravitational waves, considering relativistic effects and different gap regions. We find that the strain from the polar cap is too small, in contrast to previous results. On the other hand, the strain from the outer gap is as large as $\sim2\times10^{-24}$, enough for future gravitational-wave detection such as the Einstein Telescope. Our result presents a new approach for the future detection of gravitational waves to probe the physics in the magnetosphere.