# Microscopic simulation of xenon-based optical TPCs in the presence of molecular additives

## TL;DR

This paper presents a detailed simulation framework for electron transport and scintillation in xenon-based optical TPCs, accounting for molecular additives and comparing results with experimental data.

## Contribution

It introduces a comprehensive simulation method incorporating elementary cross sections and excited state reactions, enhancing understanding of xenon scintillation with additives.

## Key findings

- Simulation results agree with experimental observations in pure xenon and mixtures.
- The framework elucidates processes behind primary and secondary xenon scintillation.
- Insights into the effects of molecular additives on scintillation mechanisms.

## Abstract

We introduce a simulation framework for the transport of high and low energy electrons in xenon-based gaseous optical time projection chambers (OTPCs). The simulation relies on elementary cross sections (electron-atom and electron-molecule) and incorporates, in order to compute the gas scintillation, the reaction/quenching rates (atom-atom and atom-molecule) of the first 41 excited states of xenon and the relevant associated excimers, together with their radiative cascade. The results compare positively with observations made in pure xenon and its mixtures with CO$_2$ and CF$_4$ in a range of pressures from 0.1 to 10~bar. This work sheds some light on the elementary processes responsible for the primary and secondary xenon-scintillation mechanisms in the presence of additives, that are of interest to the OTPC technology.