Paper

{
  "raw_xml": "<entry>\n    <id>http://arxiv.org/abs/2603.19413v1</id>\n    <title>Ringdown modeling for effective-one-body waveforms in the test-mass limit for eccentric equatorial orbits around a Kerr black hole</title>\n    <updated>2026-03-19T19:13:46Z</updated>\n    <link href='https://arxiv.org/abs/2603.19413v1' rel='alternate' type='text/html'/>\n    <link href='https://arxiv.org/pdf/2603.19413v1' rel='related' title='pdf' type='application/pdf'/>\n    <summary>We study the plunge and merger of a non-spinning particle falling into a Kerr black hole following an eccentric planar inspiral. The dynamics is driven by an effective-one-body radiation reaction, and the corresponding numerical inspiral-merger-ringdown waveforms are obtained by solving the Teukolsky equation with the 2+1 time-domain code Teukode. We then analyze in detail the plunge and merger phases, modeling the merger-ringdown waveform using closed-form ansätze. Crucially, our modeling starts from a point closely related to the light-ring crossing, rather than from the amplitude peaks. This choice allows us to neglect the impact of the relativistic anomaly at the separatrix-crossing, and to extend the modeling to high spins and high eccentricities. We model all the multipoles with $m\\geq 1$ up to $\\ell=4$, as well as the $(2,0)$, $(5,5)$, $(5,4)$, and $(5,3)$ modes, including spherical-spheroidal mode-mixing and the beating between co-rotating and counter-rotating quasi-normal modes. The post-merger waveform model is then employed to complete an effective-one-body inspiral-plunge waveform, thus providing a complete description. Our model, built using elliptic-like configurations for the merger-ringdown phase, naturally extends to dynamical capture scenarios without any further modification. Finally, we provide insights into the extension of this framework to generic mass ratios, arguing that a time closely related to the inflection point of the (2,2) waveform frequency could be used as anchoring point for the ringdown modeling.</summary>\n    <category scheme='http://arxiv.org/schemas/atom' term='gr-qc'/>\n    <published>2026-03-19T19:13:46Z</published>\n    <arxiv:comment>38 pages, 23 figures</arxiv:comment>\n    <arxiv:primary_category term='gr-qc'/>\n    <author>\n      <name>Simone Albanesi</name>\n    </author>\n    <author>\n      <name>Sebastiano Bernuzzi</name>\n    </author>\n    <author>\n      <name>Alessandro Nagar</name>\n    </author>\n  </entry>"
}