Author(s): Romeo Felice Rosato, Francesco Crescimbeni, Sophia Yi, Emanuele Berti, and Paolo Pani We present greyring, a new model for the postmerger signal in black-hole binary coalescences based on the graybody factor of the remnant. The model accurately reproduces the full frequency-domain ringdown signal for a large set of comparable-mass, aligned-spin numerical relativity waveforms, includi… [Phys. Rev. Lett. 137, 121402] Published Tue Sep 15, 2026