# Detectability of Gravitational Waves from the Coalescence of Massive Primordial Black Holes with Initial Clustering

## TL;DR

This paper demonstrates that initial clustering of primordial black holes can greatly increase their gravitational wave coalescence detectability, especially for space-based interferometers like LISA and DECIGO/BBO, expanding detection prospects.

## Contribution

It introduces a model where initial non-Gaussian clustering enhances PBH coalescence rates, improving detection likelihood with current and future gravitational wave detectors.

## Key findings

- Clustering significantly boosts PBH coalescence event rates.
- Detection prospects are improved for space-based detectors like LISA and DECIGO/BBO.
- Ground-based detectors' parameter regimes for detection are extended.

## Abstract

We show that the effect of initial non-Gaussian clustering can significantly enhance the event rate for primordial black hole (PBH) coalescence. The impact of such clustering is studied in a specific scenario of multi-stream inflation. Initial clustering enables the possibility of detecting massive PBH coalescence by space-based gravitational wave interferometers such as LISA and DECIGO/BBO. The parameter regime for the ground-based detectors to detect PBH coalescence is also extended.