Recent searches for continuous gravitational waves

TL;DR

This paper reviews recent searches for continuous gravitational waves using Advanced LIGO data, highlighting the potential sources, current results, and future prospects in this emerging field of gravitational wave astronomy.

Contribution

It provides an overview of recent search efforts for continuous gravitational waves and discusses future sensitivity improvements and potential sources.

Findings

No continuous gravitational waves detected yet.

Current searches set upper limits on signal amplitudes.

Future detectors may improve detection prospects.

Abstract

Gravitational wave astronomy opened dramatically in September 2015 with the LIGO discovery of a distant and massive binary black hole coalescence. The more recent discovery of a binary neutron star merger, followed by a gamma ray burst and a kilonova, reinforces the excitement of this new era, in which we may soon see other sources of gravitational waves, including continuous, nearly monochromatic signals. Potential continuous wave (CW) sources include rapidly spinning galactic neutron stars and more exotic possibilities, such as emission from axion Bose Einstein "clouds" surrounding black holes. Recent searches in Advanced LIGO data are presented, and prospects for more sensitive future searches discussed.