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arXiv · 2508.21125

PRECESSION 2.1: black-hole binary spin precession on eccentric orbits

Giulia Fumagalli·Davide Gerosa·Nicholas Loutrel
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Abstract

We present version 2.1 of the public code {\sc precession}, a Python module for studying the post-Newtonian dynamics of precessing black hole binaries. In this release, we extend the code to handle eccentric orbits. This extension leverages the existing numerical infrastructure wherever possible, introducing a semi-automatic method to adapt circular-orbit functions to the eccentric case via a Python decorator. Additional new features include orbit- and precession-averaged evolutionary equations for the eccentricity, as well as revised expressions to convert between post-Newtonian separation and gravitational-wave emission frequency.

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Giulia Fumagalli, Davide Gerosa, Nicholas Loutrel. 2025-08-28. PRECESSION 2.1: black-hole binary spin precession on eccentric orbits. https://doi.org/10.1088/1742-6596%2F3177%2F1%2F012117

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