Gravitational observables for binary systems exhibit a simple polynomial dependence on the masses m1, m2 of the two scattering objects when they are written in terms of the appropriate kinematic variables in the post-Minkowskian (PM) regime. We point out that this property, combined with particle interchange symmetry, allows one to reconstruct the leading and subleading PM waveforms from their probe limit, m1≫m2. As an application, focusing on their re-expansion in the small-velocity or post-Newtonian (PN) regime, we calculate the probe-limit waveforms up to 10PN, and then exploit this observation to deduce from them the waveforms for generic masses in the center-of-mass frame up to 5PN. To this end, we employ both the amplitude-based waveform integrands and the tail formula. This combined approach simplifies substantially the PN expansion of the full subleading PM waveform.
@article{arxiv.2511.13835,
title = {Reconstructing the Gravitational Waveform from Its Probe Limit},
author = {Carlo Heissenberg and Rodolfo Russo},
journal= {arXiv preprint arXiv:2511.13835},
year = {2025}
}