NuFast-Earth: Efficient Atmospheric, Solar, and Supernova Neutrino Propagation Through the Earth

TL;DR

NuFast-Earth is a fast, flexible, and accurate algorithm and C++ implementation for computing neutrino oscillation probabilities through Earth's varying density profiles, supporting next-generation neutrino experiments.

Contribution

The paper introduces an efficient, adaptable algorithm and software for neutrino propagation calculations through Earth, improving computational speed and flexibility over previous methods.

Findings

Handles arbitrary Earth models with two density schemes

Provides significant speed-ups by reusing calculations

Supports atmospheric, solar, and supernova neutrino probabilities

Abstract

Algorithms for computing neutrino oscillation probabilities in sharply varying matter potentials such as the Earth are becoming increasingly important. As the next generation of experiments, DUNE and HyperK as well as the IceCube upgrade and KM3NeT, come online, the computational cost for atmospheric and solar neutrinos will continue to increase. To address these issues, we expand upon our previous algorithm for long-baseline calculations to efficiently handle probabilities through the Earth for atmospheric, nighttime solar, and supernova neutrinos. The algorithm is fast, flexible, and accurate. It can handle arbitrary Earth models with two different schemes for varying density profiles. We also provide a c++ implementation of the code called NuFast-Earth along with a detailed user manual. The code intelligently keeps track of repeated calculations and only recalculates what is needed on each successive call which can also help provide significant speed-ups.