2024/02/26 by Xin-Shuai Yan, Yan, Xin-Shuai, Lianghui Zhang +5
Physics and Astronomy · #Black Holes and Theoretical Physics #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #High Energy Physics - Phenomenology (hep-ph) #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions
paper · pdf · doi:10.48550/arxiv.2402.16344
openalex publication_date 2024/02/26 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Kinematics restrict the ability of rare charm decays to explore the charged Lepton Flavor Violation processes mediated by the quark-level c→ u ℓ τ transition. To fill the gap, we propose exploring new physics (NP) through the quasielastic scattering process e-p→ τ-Λc and the polarization of the τ lepton. As analyzing modes for the τ polarization, we consider the decays τ-→ π-ντ, τ-→ ρ-ντ, and τ- → ℓ-νℓντ, and show that the τ polarization components can be extracted from analyzing the kinematics of the τ visible decay products. In the framework of a general low-energy effective Lagrangian, we then perform a detailed analysis of the polarization components in various aspects and scrutinize possible NP signals. With one upcoming experimental setup, we finally demonstrate promising event rate can be expected for the cascade process and, even in the worst-case scenario -- no signals is observed at all -- it can still provide a competitive potential for constraining the NP, compared with those from the high-pT dilepton invariant mass tails at high-energy colliders.