2025/09/12 by van der Steen, Tom, Inchauspé, Henri, Hertog, Thomas +1
#FOS: Physical sciences #General Relativity and Quantum Cosmology (gr-qc) #Instrumentation and Methods for Astrophysics (astro-ph.IM)
paper · doi:10.48550/arxiv.2509.10038
The future space-based gravitational wave observatory LISA is expected to detect massive black hole binaries (MBHBs) with high signal-to-noise ratios (SNRs), ranging up to thousands. Such high-precision observations require accurate modeling of the detector response. However, current derivations of the response function neglect the motion of the spacecraft during light travel time, omitting velocity-dependent terms of order β= v/c ∼ 10-4. In this work, we derive the velocity-dependent corrections to the gravitational wave response. We analyze the contribution of the velocity-terms for MBHBs in the mass range [106,108] M\odot using a modified version of the state-of-the-art response simulator lisagwresponse. We find that corrections introduce residual SNRs up to ∼ 2 for the loudest events and fractional differences up to 0.04%, compared to lisagwresponse. While small, these effects are comparable to current waveform modeling uncertainties and imprint distinctive sky-localization signatures, making them potentially relevant for parameter estimation of high-mass MBHBs and simulation of mock datasets.