Characterizing the Galactic Gravitational Wave Background with LISA

TL;DR

This paper uses Monte Carlo simulations to analyze how LISA will detect and characterize the galactic gravitational wave background, highlighting the non-Gaussian nature caused by bright sources and proposing improved noise estimates.

Contribution

It introduces a new simulation approach for LISA's response to the galactic background and provides refined estimates of confusion noise and source resolvability.

Findings

The background is highly non-Gaussian due to bright sources.

Removing bright sources makes the remaining signal Gaussian.

New estimates of confusion noise improve previous models.

Abstract

We present a Monte Carlo simulation for the response of the Laser Interferometer Space Antenna (LISA) to the galactic gravitational wave background. The simulated data streams are used to estimate the number and type of binary systems that will be individually resolved in a 1-year power spectrum. We find that the background is highly non-Gaussian due to the presence of individual bright sources, but once these sources are identified and removed, the remaining signal is Gaussian. We also present a new estimate of the confusion noise caused by unresolved sources that improves on earlier estimates.