Updated measurement of the branching fraction of $D_s^{+}\to {\tau }^{+}{\nu }_{\tau }$ via ${\tau }^{+}\to {\pi }^{+}{\bar{\nu }}_{\tau }$

Abstract

This paper reports the study of $D_s^{+}\to {\tau }^{+}\nu$ via ${\tau }^{+}\to {\pi }^{+}{\bar{\nu }}_{\tau }$ 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 $D_s^{+}\to {\tau }^{+}{\nu }_{\tau }$ is determined to be $(5.44\pm 0.17_{\mathrm{stat}}\pm 0.13_{\mathrm{syst}})\%$. The product of the $D_s^{+}$ decay constant $f_{D_s^{+}}$ and the CKM matrix element $|V_{cs}|$ is $f_{D_s^{+}}|V_{cs}|=(248.3\pm 3.9_{\mathrm{stat}}\pm 3.1_{\mathrm{syst}}\pm 1.0_{\mathrm{input}})\mathrm{MeV}$. Combining with the $|V_{cs}|$ value obtained from the Standard Model global fit or the $f_{D_s^{+}}$ from the lattice quantum chromodynamics, we determine $|V_{cs}|=0.993\pm 0.015_{\mathrm{stat}}\pm 0.012_{\mathrm{syst}}\pm 0.004_{\mathrm{input}}$ and $f_{D_s^{+}}=(255.0\pm 4.0_{\mathrm{stat}}\pm 3.2_{\mathrm{syst}}\pm 1.0_{\mathrm{input}})\text{MeV}$. The first uncertainty is statistical, the second one is systematic and the third one is due to the input parameters, mainly the lifetime of $D_s^{+}$. 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.

References in corpus (14)

• FLAG Review 2021
• Method for detector description transformation to Unity and application in BESIII
• Leptonic decay constants fK, fD and fDs with Nf = 2+1+1 twisted-mass lattice QCD
• Study of the Standard Model with weak decays of charmed hadrons at BESIII
• Recent Progress in Leptonic and Semileptonic Decays of Charmed Hadrons
• Measurement of integrated luminosities at BESIII for data samples at center-of-mass energies between 4.0 and 4.6 GeV
• Measurement of the Absolute Branching Fractions for $D_s^{-}\to {\ell }^{-}{\bar{\nu }}_{\ell }$ and Extraction of the Decay Constant $f_{D_s}$
• Decay Constants of Pseudoscalar $D$-mesons in Lattice QCD with Domain-Wall Fermion
• Measurement of the $D_s^{+}\to {\ell }^{+}{\nu }_{\ell }$ branching fractions and the decay constant $f_{D_s^{+}}$
• Charmed and $\varphi$ meson decay constants from 2+1-flavor lattice QCD
• Measurement of the Absolute Branching Fraction of $D_s^{+}\to {\tau }^{+}{\nu }_{\tau }$ via ${\tau }^{+}\to e^{+}{\nu }_e{\bar{\nu }}_{\tau }$
• Measurement of the absolute branching fractions for purely leptonic $D_s^{+}$ decays
• Measurement of the branching fraction of leptonic decay $D_s^{+}\to {\tau }^{+}{\nu }_{\tau }$ via ${\tau }^{+}\to {\pi }^{+}{\pi }^0{\bar{\nu }}_{\tau }$
• Measurement of the branching fraction of $D_s^{+}\to {\tau }^{+}{\nu }_{\tau }$ via ${\tau }^{+}\to {\mu }^{+}{\nu }_{\mu }\overline{{\nu }_{\tau }}$

Cited by in corpus (3)

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• Charm Physics at the Super $\tau$-Charm Factory
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