Global Analysis of LISA Data with Galactic Binaries and Massive Black Hole Binaries

Abstract

The Laser Interferometer Space Antenna (LISA) is a planned space-based observatory to measure gravitational waves in the millihertz frequency band. This frequency band is expected to be dominated by signals from millions of Galactic binaries and tens of merging massive black hole binaries. The LISA Data Challenge 2a is focused on robust signal extraction from a blend of these two types of gravitational wave signals. Here, we introduce a novel high performance and cost-effective global fit pipeline extracting and characterizing galactic binary and massive black hole binary signals and estimate the noise of the residual. We perform the pipeline in a time-evolving weekly analysis starting with an observation time of 1 week until we reach a full year. As expected we detect more galactic binaries and massive black hole binaries bringing the noise estimate of the residual closer to the instrument noise with each week of additional observation time. Furthermore, we present a novel maximum likelihood estimate-based algorithm for extracting multiple massive black hole binaries. Additionally, we demonstrate a massive black hole binary signal extraction with a more accurate LISA response, considering higher harmonic modes, in a noisy data set.