Searching for Mini Extreme Mass Ratio Inspirals with Gravitational-Wave Detectors

TL;DR

This paper explores the potential of ground-based gravitational-wave detectors like LIGO/Virgo to identify mini extreme mass ratio inspirals involving exotic compact objects, using a novel Hough Transform-based search method.

Contribution

It introduces a new search technique for detecting mini-EMRIs with ground-based detectors, capable of probing a wide range of exotic compact objects.

Findings

LIGO/Virgo can detect mini-EMRIs with current and future sensitivities.

The Hough Transform method effectively tracks quasi power-law signals during inspiral.

Many exotic compact objects are within reach of current gravitational-wave searches.

Abstract

A compact object with a mass $\mathcal{O}(1 \sim 1000) M_{\odot}$, such as a black hole of stellar or primordial origin or a neutron star, and a much lighter exotic compact object with a subsolar mass could form a non-standard mini extreme mass ratio inspiral (EMRI) and emit gravitational waves within the frequency band of ground-based gravitational-wave detectors. These systems are extremely interesting because detecting them would definitively point to new physics. We study the capability of using LIGO/Virgo to search for mini-EMRIs and find that a large class of exotic compact objects can be probed at current and design sensitivities using a method based on the Hough Transform that tracks quasi power-law signals during the inspiral phase of the mini-EMRI system.