Astro Seminar: Giulia Fumagalli

Date: November 10, 2025

Time: 14:15

Location: Auditorium A

Speaker: Giulia Fumagalli (University of Milano-Bicocca).

Title: Dynamics of spin-precessing and eccentric compact binaries

Abstract: The most generic configuration for a compact binary system involves spins oriented isotropically and eccentric orbits. Specifically, measuring eccentricity and spin misalignment (i.e., spin precession) through gravitational waves is essential for understanding the origin of compact binaries, as many proposed formation channels predict specific values for these parameters. However, how can we propagate the predictions of these formation pathways into the regime where we observe compact binaries? Or, conversely, how do we connect the parameters we measure at binary merger to the initial conditions of the binary at formation, considering that billions of years can pass between these stages? In this talk, I will present a post-Newtonian framework that efficiently models the complete evolution of spin-precessing and eccentric compact binaries from formation to merger. Using this, we reveal an interplay between spin orientations and eccentricity, finding that the former evolves differently than in the well-known case of zero eccentricity. I will demonstrate that this has significant implications for the inference of formation channels based on current and future gravitational wave observations. Finally, I will present the possible fragility of this framework, which is based on a multi-timescale approach, in the case of highly eccentric binaries, where standard orbit-averaged equations cannot be consistently applied.