COSE$\nu$: A Collective Oscillation Simulation Engine for Neutrinos

TL;DR

COSEν is a simulation engine designed to numerically solve complex equations governing neutrino flavor conversions, employing advanced numerical methods and validated through comparison with theoretical solutions, with performance optimized for CPUs and GPUs.

Contribution

This paper presents the implementation of COSEν, a novel simulation code for neutrino collective oscillations, detailing numerical methods, validation, error analysis, and performance benchmarking.

Findings

Code accurately reproduces theoretical solutions.

Error behavior analyzed for different simulation parameters.

Performance benchmarks show efficiency on CPUs and GPUs.

Abstract

We introduce the implementation details of the simulation code \cosenu, which numerically solves a set of non-linear partial differential equations that govern the dynamics of neutrino collective flavor conversions. We systematically provide the details of both the finite difference method supported by Kreiss-Oliger dissipation and the finite volume method with seventh order weighted essentially non-oscillatory scheme. To ensure the reliability of the code, we perform the comparison of the simulation results with theoretically obtainable solutions. In order to understand and characterize the error accumulation behavior of the implementations when neutrino self-interactions are switched on, we also analyze the evolution of the deviation of the conserved quantities for different values of simulation parameters. We report the performance of our code with both CPUs and GPUs. The public version of the \cosenu~package is available at \url{https://github.com/COSEnu/COSEnu}.