Neutron Star Extreme Matter Observatory: A kilohertz-band gravitational-wave detector in the global network

TL;DR

The paper proposes NEMO, a specialized gravitational-wave detector optimized for kilohertz frequencies, to study nuclear matter in neutron star mergers and post-merger remnants, enhancing detection capabilities and scientific insights.

Contribution

It introduces the NEMO detector concept, combining high power, quantum squeezing, and a tailored topology to achieve high-frequency sensitivity at lower cost.

Findings

NEMO's sensitivity is comparable to third-generation detectors above 1 kHz.

Expected detection rate of post-merger remnants increases from once every few decades to several per year.

Potential to observe supernovae and exotic objects through gravitational waves.

Abstract

Gravitational waves from coalescing neutron stars encode information about nuclear matter at extreme densities, inaccessible by laboratory experiments. The late inspiral is influenced by the presence of tides, which depend on the neutron star equation of state. Neutron star mergers are expected to often produce rapidly-rotating remnant neutron stars that emit gravitational waves. These will provide clues to the extremely hot post-merger environment. This signature of nuclear matter in gravitational waves contains most information in the 2-4 kHz frequency band, which is outside of the most sensitive band of current detectors. We present the design concept and science case for a neutron star extreme matter observatory (NEMO): a gravitational-wave interferometer optimized to study nuclear physics with merging neutron stars. The concept uses high circulating laser power, quantum squeezing and a detector topology specifically designed to achieve the high-frequency sensitivity necessary to probe nuclear matter using gravitational waves. Above one kHz, the proposed strain sensitivity is comparable to full third-generation detectors at a fraction of the cost. Such sensitivity changes expected event rates for detection of post-merger remnants from approximately one per few decades with two A+ detectors to a few per year, and potentially allows for the first gravitational-wave observations of supernovae, isolated neutron stars, and other exotica.