Speaker
Description
The Mu3e Experiment at the Paul Scherrer Institut (PSI) searches for the charged-lepton-flavour-violating decay $\mu^+ \to \text{e}^+ \text{e}^- \text{e}^+$. Using a high-intensity muon beam, delivering up to $10^8$ muons per second, the experiment aims to improve the exclusion limit of $\mu^+ \to \text{e}^+ \text{e}^- \text{e}^+$ by four orders of magnitude. A main challenge of the experiment is the distinction between signal events and the combinatorial background, which requires accurate tracking and vertex resolution.
The General Triplet Track Fit (GTTF) [1] is a track fit based on hit triplets that includes multiple scattering uncertainties, as well as position uncertainties, and gives an analytical solution for the track parameters. By treating the decay vertex position as an additional pseudo-hit, the GTTF allows for the simultaneous fitting of both the vertex position and the track parameters.
This poster presents the performance of the vertex fit for simulated decays in a toy detector. The performance is evaluated for hit uncertainty dominated, and multiple scattering uncertainty dominated regimes. Furthermore, results from the reconstruction of simulated signal decays for the Mu3e Experiment will be shown.
[1] A. Schöning, 2025, A General Track Fit based on Triplets, https://doi.org/10.1016/j.nima.2025.170391