Targeted Search for Gravitational Waves from Highly Spinning Light Compact Binaries

TL;DR

This paper conducts a targeted search for gravitational waves from highly spinning, light compact binaries, including neutron stars and black holes, using LIGO and Virgo data, but finds no new signals beyond known events.

Contribution

It introduces a specialized search for high-spin, light binaries, expanding the parameter space beyond previous gravitational wave searches.

Findings

Detected known events GW170817 and GW200115

No additional mergers found in the data

Set constraints on the merger rate of such binaries

Abstract

Searches for gravitational waves from compact-binary mergers, which to date have reported $\sim100$ observations, have previously ignored binaries whose components are both consistent with the mass of neutron stars $(1 M_\odot$ to $ 2 M_\odot)$ and have high dimensionless spin $>0.05$. While previous searches targeted sources that are representative of observed neutron star binaries in the galaxy, it is already known that neutron stars can regularly be spun up to a dimensionless spin of $\sim0.4$, and in principle reach up to $\sim0.7$ before breakup would occur. Furthermore, there may be primordial black hole binaries or exotic formation mechanisms to produce light black holes. In these cases, it is possible for the binary constituent to be spun up beyond that achievable by a neutron star. A single detection of this type of source would reveal a novel formation channel for compact-binaries. To determine if there is evidence for any such sources, we use PyCBC to conduct a targeted search of LIGO and Virgo data for light compact objects with high spin. Our analysis detects previously known observations GW170817 and GW200115; however, we report no additional mergers. The most significant candidate, not previously known, is consistent with the noise distribution, and so we constrain the merger rate of spinning light binaries.