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arXiv · 2312.15495

Track reconstruction for the COMET Phase-II experiment with ACTS

Abstract

An implementation of A Common Tracking Software (ACTS) toolkit for signal electron reconstruction for the COMET muon to electron conversion experiment is discussed. The COMET experiment in J-PARC, Japan, will search for neutrinoless conversion of muons into electrons in the field of an aluminium nucleus, a lepton flavour violating process, aiming target sensitivity of $10^{-17}$. To achieve its scientific goals, the experiment requires a reconstructed momentum resolution of lower than 150 keV/c. For the first time by applying ACTS to signal events in the 100 MeV energy range with multiple-turn trajectories in the presence of background events, it is found that the reconstruction efficiency is around 14\% with no fake reconstructed events. The implementation details, performance, and issues of ACTS in the context of COMET are presented.

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Amaia Razquin, MyeongJae Lee. 2023-12-24. Track reconstruction for the COMET Phase-II experiment with ACTS. https://doi.org/10.1088/1748-0221%2F19%2F01%2Fp01011

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