Calzone: A Geant4 Python wrapper for the simulation of outdoor particle detectors

The transport of high-energy particles (e.g., gamma-rays) through ordinary matter is an inherently stochastic process, with individual collisions described within the framework of quantum field theory.The resolution of such transport problems is facilitated by the use of Monte Carlo methods, denoted Monte Carlo particles transport (MCPT) herein.In particular, the Geant4 software (Agostinelli et al., 2003;Allison et al., 2006Allison et al., , 2016) is an established MCPT C++ library for simulating the passage of high-energy particles through matter.Calzone (CALorimeter ZONE) is a MCPT Python package built on top of Geant4.It was developed in the context of geosciences with the objective of studying the emission of radioactivity from volcanoes (Terray et al., 2020), and in particular to simulate the response of gamma spectrometers deployed in the field.To this end, Calzone was developed in conjunction with Goupil (Niess et al., 2024), a backward gamma transport engine, and is interoperable with the latter.Yet, both packages can be used entirely independently, if necessary.