Search for the weak decay ${\eta }^{\prime }\to K^{\pm }{\pi }^{\mp }$ and precise measurement of the branching fraction $\mathcal{B}(J/\psi \to \varphi {\eta }^{\prime })$

Abstract

We present the first search for the rare decay of ${\eta }^{\prime }$ into $K^{\pm }{\pi }^{\mp }$ in $J/\psi \to \varphi {\eta }^{\prime }$, using a sample of $1.3\times 10^9$ $J/\psi$ events collected with the BESIII detector. No significant signal is observed, and the upper limit at the 90\% confidence level for the ratio $\frac{\mathcal{B}({\eta }^{\prime }\to K^{\pm }{\pi }^{\mp })}{\mathcal{B}({\eta }^{\prime }\to \gamma {\pi }^{+}{\pi }^{-})}$ is determined to be $1.3\times 10^{-4}$. In addition, we report the measurement of the branching fraction of $J/\psi \to \varphi {\eta }^{\prime }$ to be $(5.10\pm 0.03(\text{stat.})\pm 0.32(\text{syst.}))\times 10^{-4}$, which agrees with previous results from BESII.

References in corpus (10)

• A Unified Approach to the Classical Statistical Analysis of Small Signals
• Design and Construction of the BESIII Detector
• The Precision Monte Carlo Event Generator KK For Two-Fermion Final States In e+e- Collisions
• Coherent Exclusive Exponentiation For Precision Monte Carlo Calculations
• Resonances in $J/\psi \to \varphi {\pi }^{+}{\pi }^{-}$ and $\varphi K^{+}{K}^{-}$
• Search for hadronic transition ${\chi }_{cJ}\to {\eta }_c{\pi }^{+}{\pi }^{-}$ and observation of ${\chi }_{cJ}\to K\bar{K}\pi \pi \pi$
• Study of ${\chi }_{cJ}$ radiative decays into a vector meson
• Search for a light exotic particle in J/psi radiative decays
• Measurement of ${\eta }^{\prime }\to {\pi }^{+}{\pi }^{-}{e}^{+}{e}^{-}$ and ${\eta }^{\prime }\to {\pi }^{+}{\pi }^{-}{\mu }^{+}{\mu }^{-}$
• Measurements of J/psi decays into phi pi^0, phi eta, and phi eta^prime

Cited by in corpus (5)

• An overview of $\eta$ and ${\eta }^{\prime }$ decays at BESIII
• Event generators for $\eta /{\eta }^{\prime }$ decays at BESIII
• Measurement of Branching Fractions of $\psi (3686)\to \varphi {\eta }^{\prime },\varphi f_1(1285)$ and $\varphi \eta (1405)$
• Rare weak decays of ${\eta }^{\prime }\to K\pi$
• Search for sub-GeV invisible particles in inclusive decays of $J/\psi$ to $\varphi$