Astrophysics, Relativity, and Cosmology Seminar - Alejandro Cárdenas-Avendaño (Wake Forest University) "Resonance-Driven Flux Modifications in Extreme-Mass-Ratio Inspirals"

Extreme-mass-ratio inspirals (EMRIs), systems where a stellar-mass compact object spirals into a supermassive black hole, are primary targets for the upcoming space-based gravitational-wave detector LISA. As the smaller body inspirals, it crosses transient orbital resonances where its radial and polar orbital frequencies hit simple integer ratios. These brief crossings deliver phase-dependent "kicks" to the system's energy, angular momentum, and Carter constant, knocking the inspiral off its standard trajectory and altering the emitted gravitational-wave signal. In this talk, I present a systematic characterization of these transient resonance effects across the EMRI parameter space, drawing on the largest dataset of Teukolsky-derived resonance coefficients to date. By numerically solving the Teukolsky equation in the frequency domain and coherently combining degenerate harmonics, we uncover how these flux modifications vary with black hole spin, orbital eccentricity, and inclination, with a focus on the dynamically critical 2:1 and 3:2 resonances. I will explore the physical mechanisms driving these variations and finish by discussing how high-precision resonance modeling serves as an essential input for building accurate EMRI waveform templates.