2023/03/22 by BESIII Collaboration, M. Ablikim, Ablikim, M. +712
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions
paper · pdf · doi:10.48550/arxiv.2303.12600
openalex publication_date 2023/03/22 · openalex created_date 2023/03/25 · openalex updated_date 2026/07/30
This paper reports the study of Ds+→ τ+ν via τ+→π+ντ using a boosted decision tree method, with 7.33 fb-1 of e+e- collision data collected by the BESIII detector at center-of-mass energies between 4.128 and 4.226~GeV. The branching fraction of Ds+→ τ+ντ is determined to be (5.44±0.17\rm stat±0.13\rm syst)%. The product of the Ds+ decay constant fDs+ and the CKM matrix element |Vcs| is fDs+|Vcs| = (248.3±3.9\rm stat±3.1\rm syst±1.0\rm input)~MeV. Combining with the |Vcs| value obtained from the Standard Model global fit or the fDs+ from the lattice quantum chromodynamics, we determine |Vcs| = 0.993±0.015\rm stat±0.012\rm syst±0.004\rm input and fDs+ = (255.0±4.0\rm stat±3.2\rm syst±1.0\rm input)~MeV. The first uncertainty is statistical, the second one is systematic and the third one is due to the input parameters, mainly the lifetime of Ds+. All results obtained in this work supersede the BESIII previous results based on 6.32 fb-1 of e+e- collision data taken at center-of-mass energies between 4.178 and 4.226~GeV.