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arXiv · 2302.04950

Monte Carlo modelling of the linear Breit-Wheeler process within the GEANT4 framework

R. A. Watt·S. J. Rose·B. Kettle·S. P. D. Mangles
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Abstract

A linear Breit-Wheeler module for the code Geant4 has been developed. This allows signal-to-noise ratio calculations of linear Breit-Wheeler detection experiments to be performed within a single framework. The interaction between two photon sources is modelled by treating one as a static field, then photons from the second source are sampled and tracked through the field. To increase the efficiency of the module, we have used a Gaussian process regression, which can lead to an increase in the calculation rate by a factor of up to 1000. To demonstrate the capabilities of this module, we use it to perform a parameter scan, modelling an experiment based on that recently reported by Kettle et al. [1]. We show that colliding $50\,$fs duration $\gamma$-rays, produced through bremsstrahlung emission of a $100\,$pC, $2\,$GeV laser wakefield accelerator beam, with a $50\,$ps X-ray field, generated by a germanium burn-through foil heated to temperatures $>\,150\,$eV, this experiment is capable of producing $>1\,$ Breit-Wheeler pair per shot.

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R. A. Watt, S. J. Rose, B. Kettle, S. P. D. Mangles. 2023-02-09. Monte Carlo modelling of the linear Breit-Wheeler process within the GEANT4 framework. https://doi.org/10.1103/physrevaccelbeams.26.054601

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