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This content will become publicly available on February 26, 2026

Title: Recovering Injected Astrophysics from the LISA Double White Dwarf Binaries
Abstract We present the successful recovery of common-envelope ejection efficiency assumed in a simulated population of double white dwarf (DWD) binaries like those which may be observed by the future Laser Interferometer Space Antenna (LISA) mission. We simulate the formation of DWD binaries by using the COSMIC population synthesis code to sample binary formation conditions such as initial mass function, metallicity of star formation, initial orbital period, and initial eccentricity. These binaries are placed in the m12i synthetic Milky Way–like galaxy, and their signal-to-noise ratio (SNR) for the LISA instrument is estimated, considering a Galactic gravitational-wave foreground informed by the population. Through the use of Fisher estimates, we construct a likelihood function for the measurement error of the LISA-bright DWD binaries (≥20 SNR,fGW≥ 5 mHz), in their gravitational-wave frequency (fGW) and chirp mass. By repeating this process for different assumptions of the common-envelope ejection efficiency, we apply Bayesian hierarchical inference to find the best match to an injected astrophysical assumption for a fiducial population model. We conclude that the impact of common-envelope ejection efficiency on the mass-transfer processes involved in DWD formation may be statistically relevant in the future observed LISA population, and that constraints on binary formation may be found by comparing simulated populations to a future observed population.  more » « less
Award ID(s):
2012057 2206321 2309172
PAR ID:
10615793
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
American Astronomical Society
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
981
Issue:
1
ISSN:
0004-637X
Page Range / eLocation ID:
66
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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