# Pulsar Timing Probes of Primordial Black Holes and Subhalos

## TL;DR

Pulsar timing arrays can detect or constrain primordial black holes and subhalos across a wide mass range, offering a new method to probe dark matter subcomponents and their properties.

## Contribution

This study demonstrates the sensitivity of pulsar timing arrays, especially the Square Kilometer Array, to primordial black holes and subhalos, providing constraints on their abundance and density.

## Key findings

- SKA can constrain primordial black holes as a dark matter component.
- PTAs can detect less dense objects than lensing techniques.
- Constraints on subhalo concentration parameters are achievable.

## Abstract

Pulsars act as accurate clocks, sensitive to gravitational redshift and acceleration induced by transiting clumps of matter. We study the sensitivity of pulsar timing arrays (PTAs) to single transiting compact objects, focusing on primordial black holes and compact subhalos in the mass range from $10^{-12} M _{\odot}$ to well above $100~M_\odot$. We find that the Square Kilometer Array can constrain such objects to be a subdominant component of the dark matter over this entire mass range, with sensitivity to a dark matter sub-component reaching the sub-percent level over significant parts of this range. We also find that PTAs offer an opportunity to probe substantially less dense objects than lensing because of the large effective radius over which such objects can be observed, and we quantify the subhalo concentration parameters which can be constrained.