Measurement of the inclusive branching fraction for $\psi (3686)\to K_S^0+\text{anything}$

Abstract

Using 5.9~pb${}^{-1}$ of $e^{+}{e}^{-}$ annihilation data collected at center-of-mass energies from 3.640 to 3.701 GeV with the BESIII detector at the BEPCII Collider, we measure the observed cross sections of $e^{+}{e}^{-}\to K_S^{0}X$ (where $X=\text{anything}$). From a fit to these observed cross sections with the sum of continuum and $\psi (3686)$ and $J/\psi$ Breit-Wigner functions and considering initial state radiation and the BEPCII beam energy spread, we obtain for the first time the product of $\psi (3686)$ leptonic width and inclusive decay branching fraction ${\Gamma }_{\psi (3686)}^{ee}\mathcal{B}(\psi (3686)\to K_S^{0}X)=(373.8\pm 6.7\pm 20.0)$ eV, and assuming ${\Gamma }_{\psi (3686)}^{ee}$ is $(2.33\pm 0.04)$ keV from PDG value, we measure $\mathcal{B}(\psi (3686)\to K_S^{0}X)=(16.04\pm 0.29\pm 0.90)\%$, where the first uncertainty is statistical and the second is systematic.

arXiv comment11 pages, 5 figures

References in corpus (6)

• Design and Construction of the BESIII Detector
• Coherent Exclusive Exponentiation For Precision Monte Carlo Calculations
• Matching perturbative and Parton Shower corrections to Bhabha process at flavour factories
• Measurements of the cross sections for $e^{+}{e}^{-}\to \mathrm{hadrons}$ at 3.650, 3.6648, 3.773 GeV and the branching fraction for $\psi (3770)\to \mathrm{non}-D\bar{D}$
• Determination of the number of ${\psi }^{\prime }$ event at BESIII
• Error Estimates on Parton Density Distributions