Probing the parameter constraints on astrophysical environments of intermediate and extreme mass ratio inspiral binaries with LISA
Abstract
The future space-borne Laser Interferometer Space Antenna (LISA) would allow detection of intermediate (IMRI) and extreme mass ratio inspirals (EMRI) via their gravitational wave (GW) emission. However, these binaries may live in nontrivial astrophysical environments, affecting their GW emission and thereby complicating detection and parameter estimation. By using Fisher matrix analysis, we calculate the uncertainties in the environmental density of inspirals with different mass ratios. We study several environmental effects affecting GW emission ‒ gravitational pull, collisionless accretion, and gravitational drag ‒ and find a log-log relationship between the uncertainties and the primary mass of the binary. By using overlap analysis, we also get the signal-to-noise ratios (SNR) of the difference between a vacuum and an environmentally-modified waveform. We find that the dephasing brought about by environmental effects may be detectable within LISA's 4-year mission lifetime, especially for EMRIs.