A New Full 3-D Model of Cosmogenic Tritium $^3$H Production in the Atmosphere (CRAC:3H)

TL;DR

The paper introduces CRAC:3H, a comprehensive Monte Carlo model for calculating cosmogenic tritium production in the atmosphere, accounting for various cosmic ray spectra and particle types, aiding atmospheric and hydrological studies.

Contribution

It presents the first full 3-D Monte Carlo model for $^3$H production that includes particles heavier than protons and can compute location-specific production rates.

Findings

First model to include heavy cosmic-ray particles

Allows location and time-specific $^3$H production calculations

Provides a practical numerical recipe for users

Abstract

A new model of cosmogenic tritium ($^3$H) production in the atmosphere is presented. The model belongs to the CRAC (Cosmic-Ray Atmospheric Cascade) family and is named as CRAC:3H. It is based on a full Monte-Carlo simulation of the cosmic-ray induced atmospheric cascade using the Geant4 toolkit. The CRAC:3H model is able, for the first time, to compute tritium production at any location and time, for any given energy spectrum of the primary incident cosmic ray particles, explicitly treating, also for the first time, particles heavier than protons. This model provides a useful tool for the use of $^3$H as a tracer of atmospheric and hydrological circulation. A numerical recipe for practical use of the model is appended.