Prospects of fast timing detectors for particle identification at future Higgs factories

Abstract

We present an overview of a study on precise mass reconstruction and identification of charged hadrons (π ± , K ± , p) using time-of-flight measurements in the electromagnetic calorimeter of a typical Higgs factory detector. Time-of-flight measurements can take advantage of fast timing Si sensors with a time resolution in the order of 10 ps. A precise time-of-flight measurement might contribute to the kaon mass determination and can improve particle identification in the momentum regions inaccessible for the dE/dx method. In this contribution, we discuss the current status and the challenges of the time-of-flight approach for a precise reconstruction of charged hadron masses.

Observing true tauonium via two-photon fusion at $e^+e^-$ and hadron colliders

“…At FCC-ee Z-pole energies, the Lorentz boost is larger (βγ ≈ 3) and results in a mean tauonium decay length of L vtx ≈ 30 µm, with counts expected in the tail up to ∼0.1 mm. On the one hand, the diphoton vertex pointing capabilities are coarse, in the 1-cm range for LHC-type calorimeters, unless one uses converted photons and/or high-precision time-of-flight (separating mm distances requires few ps timing resolution) [54]. On the other hand, one could alternatively exploit the T 0 → e + e − γ and T 0 → µ + µ − γ Dalitz decays, with combined branching fraction of O(3%) [11], leading to O(100) or O(20) signal counts at FCC-ee and Belle-II, respectively.…”