3 Jun 2024 | Stefan H. Strub, Luigi Ferraioli, Cédric Schmelzbach, Simon C. Stähler, and Domenico Giardini
This paper presents a novel global fit pipeline for extracting and characterizing galactic binaries (GBs) and massive black hole binaries (MBHBs) from LISA data. The pipeline is designed to handle the complex task of signal extraction from a blend of these two types of gravitational wave signals. The method is tested on the LISA Data Challenge 2a (LDC2a), which includes a combination of 15 MBHBs, 30 million GBs, and instrument noise. The pipeline is implemented in a time-evolving weekly analysis, starting with one week of observation data and extending to a full year. As more data is collected, the pipeline detects more GBs and MBHBs, reducing the residual noise closer to the instrument noise level.
The pipeline incorporates a novel maximum likelihood estimate (MLE)-based algorithm for extracting multiple MBHBs and uses a more accurate LISA response that includes higher harmonic modes. The algorithm is tested on the LDC1-1 data set, which contains a single MBHB signal and simulated instrument noise, and on the LDC2a data set. The results show that the pipeline effectively extracts MBHBs and GBs, with the match ratio stabilizing at around 85% to 88% after 16 weeks of observation. The pipeline also demonstrates robustness, with results showing consistent performance across different seeds and observation times.
The pipeline is computationally efficient, with a low cost of analysis, allowing for weekly updates as new data is incorporated. The results highlight the importance of mission duration in the effective recovery of GBs, especially at frequencies around 4 mHz. The pipeline is publicly available and can be used for future research, with potential extensions to include other GW signal types and pre-merger MBHB parameter estimation. The method provides a robust, high-quality signal extraction and noise estimation approach for LISA data.This paper presents a novel global fit pipeline for extracting and characterizing galactic binaries (GBs) and massive black hole binaries (MBHBs) from LISA data. The pipeline is designed to handle the complex task of signal extraction from a blend of these two types of gravitational wave signals. The method is tested on the LISA Data Challenge 2a (LDC2a), which includes a combination of 15 MBHBs, 30 million GBs, and instrument noise. The pipeline is implemented in a time-evolving weekly analysis, starting with one week of observation data and extending to a full year. As more data is collected, the pipeline detects more GBs and MBHBs, reducing the residual noise closer to the instrument noise level.
The pipeline incorporates a novel maximum likelihood estimate (MLE)-based algorithm for extracting multiple MBHBs and uses a more accurate LISA response that includes higher harmonic modes. The algorithm is tested on the LDC1-1 data set, which contains a single MBHB signal and simulated instrument noise, and on the LDC2a data set. The results show that the pipeline effectively extracts MBHBs and GBs, with the match ratio stabilizing at around 85% to 88% after 16 weeks of observation. The pipeline also demonstrates robustness, with results showing consistent performance across different seeds and observation times.
The pipeline is computationally efficient, with a low cost of analysis, allowing for weekly updates as new data is incorporated. The results highlight the importance of mission duration in the effective recovery of GBs, especially at frequencies around 4 mHz. The pipeline is publicly available and can be used for future research, with potential extensions to include other GW signal types and pre-merger MBHB parameter estimation. The method provides a robust, high-quality signal extraction and noise estimation approach for LISA data.