Recently, Pulsar Timing Arrays (PTAs) reported a signal at nanohertz frequencies consistent with a stochastic gravitational wave background. Here, I show that the Brownian motion of the Sun as a result of its random gravitational interactions with the cluster of thousands of unmodeled Main-belt asteroids of diameters <80km, combined with small inaccuracies in the estimated masses of larger asteroids, introduces timing noise for pulsars which is up to 20% of the reported signal at frequencies of ~1/(few-years). The asteroid contribution needs to be modeled better in order to obtain accurate inferences from the PTA signal.
@article{arxiv.2405.05410,
title = {Pulsar Timing Noise from Brownian Motion of the Sun},
author = {Abraham Loeb},
journal= {arXiv preprint arXiv:2405.05410},
year = {2024}
}
Comments
Accepted for publication in ApJL, 5 pages (final version)