ULYSSES, universal LeptogeneSiS equation solver: Version 2

Abstract

ULYSSES is a Python package that calculates the baryon asymmetry produced from leptogenesis in the context of a type-I seesaw mechanism. In this release, the new features include code which solves the Boltzmann equations for low-scale leptogenesis; the complete Boltzmann equations for thermal leptogenesis applying proper quantum statistics without assuming kinetic equilibrium of the right-handed neutrinos; and, primordial black hole-induced leptogenesis. ULYSSES version 2 has the added functionality of a pre-provided script for a two-dimensional grid scan of the parameter space. As before, the emphasis of the code is on user flexibility, rapid evaluation and is publicly available at https://github.com/earlyuniverse/ulysses. Program summaryProgram Title: ULYSSESCPC Library link to program files:https://doi.org/10.17632/rzd24f34h2.2Developer's repository link:https://github.com/earlyuniverse/ulysses/tree/master/ulyssesLicensing provisions: MITProgramming language: Python3Journal reference of previous version: Comput. Phys. Commun. 262 (2021) 107813Does the new version supersede the previous version?: YesReasons for the new version: Inclusion of additional effects in Boltzmann equations.Summary of revisions: Low scale leptogenesis, PBH-induced leptogenesis, and complete leptogenesis equations (non-momentum integrated equations) are provided.Nature of problem: Solve the Boltzmann equations for thermal, resonant and low-scale leptogenesis through a set of coupled ordinary differential equations.Solution method: Boltzmann equations are solved using a combination of odeint and solve_ivp in Python3.