Related papers: Study of the Dalitz decay $J/\psi \to e^+e^- \eta$

Two types of pseudoscalar quarkonium electromagnetic decay processes, i.e. decay to a lepton pair, and to a lepton pair plus a photon (Dalitz decay), are analyzed at the leading order in NRQCD expansion. The former type of processes, highly…

We search for the leptonic decay $D^+\to e^+\nu_{e}$ using an $e^+e^-$ collision data sample with an integrated luminosity of 20.3~fb$^{-1}$ collected with the BESIII detector at the center-of-mass energy of 3.773~GeV. No significant signal…

Precision measurements of the semileptonic decays $D_s^+ \to \eta e^+ \nu_e$ and $D_s^+ \to \eta^\prime e^+ \nu_e$ are performed with 7.33\,fb$^{-1}$ of $e^+e^-$ collision data collected at center-of-mass energies between 4.128 and 4.226…

Data samples corresponding to the isospin-violating decay $D_s^{*+}\to D_s^+ \pi^0$ and the decays $D_s^{*+}\to D_s^+\gamma$, $D^{*0}\to D^0\pi^0$ and $D^{*0}\to D^0\gamma$ are reconstructed using 90.4 ${\rm fb}^{-1}$ of data recorded by…

Using a data sample of $(2712.4 \pm 14.3) \times 10^{6}$ $\psi(3686)$ events collected with the BESIII detector operating at the BEPCII collider, we report the first observation of the decays $\chi_{cJ}\to 2K^+ 2K^- \omega$ and…

Based on the data sample of $448.1\times10^{6}$ $\psi(3686)$ events collected with the BESIII detector at BEPCII, we present a study of the decays $\psi(3686)\rightarrow\gamma\chi_{cJ}\rightarrow\gamma\bar{p}K^{*+}\Lambda+c.c.$ and…

Using $1310.6\times10^{6}$ $J/\psi$ and $448.1\times10^{6}$ $\psi(3686)$ events collected with the BESIII detector, the branching fractions of $J/\psi$ and $\psi(3686)$ decays to $\Sigma^{+}\overline{\Sigma}^{-}$ are measured to be $(10.61…

We study the processes $\gamma \gamma \to K^0_S K^{\pm}\pi^{\mp}$ and $\gamma \gamma \to K^+ K^- \pi^0$ using a data sample of 519~$fb^{-1}$ recorded with the BaBar detector operating at the SLAC PEP-II asymmetric-energy $e^+ e^-$ collider…

Based on a sample of $2.25\times 10^{8} J/\psi$ events taken with the BESIII detector at the BEPCII collider, we present the results of a study of the decay $J/\psi\to \eta \phi\pi^{+}\pi^{-}$. The $Y(2175)$ resonance is observed in the…

Using $(106.41\pm 0.86) \times 10^{6}$ $\psi(3686)$ events collected with the BESIII detector at BEPCII, we study for the first time the decay $\chi_{cJ}\to\eta'K^+K^-$, where $\eta'\to\gamma\rho^{0}$ and $\eta'\to\eta\pi^+\pi^-$. A partial…

Using $(2712.4\pm14.3)\times10^{6}$ $\psi(3686)$ events collected with the BESIII detector at the BEPCII collider, the decay $\eta_c\to\gamma\gamma$ in $J/\psi\to\gamma\eta_c$ is observed. We determine the product branching fraction…

Using 16 energy points of $e^{+}e^{-}$ annihilation data collected in the vicinity of the $J/\psi$ resonance with the BESIII detector and with a total integrated luminosity of around 100 pb$^{-1}$, we study the relative phase between the…

Based on $448.1 \times 10^6$ $\psi(3686)$ events collected with the BESIII detector, the decays $\psi(3686)\to\gamma\chi_{cJ}, \chi_{cJ} \to \gamma\gamma~(J=0, 1, 2)$ are studied. The decay branching fractions of $\chi_{c0,c2} \to…

A study of $B^{0}_{s} \to \eta_{c} \phi$ and $B^{0}_{s} \to \eta_{c} \pi^{+}\pi^{-}$ decays is performed using $pp$ collision data corresponding to an integrated luminosity of 3.0$\,\rm fb^{-1}$, collected with the LHCb detector in Run~1 of…

We have studied the vector to pseudoscalar conversion decay phi -> eta e+e-, with eta -> pi0pi0pi0, with the KLOE detector at DAPHNE. The data set of 1.7 fb-1 of e+e- collisions at sqrt(s)~Mphi contains a clear conversion decay signal of…

In this paper, the dilepton electromagnetic decays $\chi_{cJ}(1P) \to J/\psi e^+e^-$ and $\chi_{cJ}(1P) \to J\psi \mu^+\mu^-$, where $\chi_{cJ}$ denotes $\chi_{c0}$, $\chi_{c1}$ and $\chi_{c2}$, are calculated systematically in the improved…

Using a sample of $(27.12\pm 0.14) \times 10^{8}$ $\psi(3686)$ events collected with the BESIII detector, the decay $\psi(3686) \to \Lambda \bar{\Lambda} \eta'$ with $\eta'$ subsequently decaying into $\gamma \pi^+ \pi^-$ and $\eta \pi^+…

The decays $J/\psi\to p\bar{p}$ and $J/\psi\to n\bar{n}$ have been investigated with a sample of 225.2 million $J/\psi$ events collected with the BESIII detector at the BEPCII $e^+e^-$ collider. The branching fractions are determined to be…

In this paper, we present an improved calculation for the decay rate of the rare $Z$-boson decay into $J/\psi + J/\psi$. This decay is dominated by the photon fragmentation mechanism, i.e., the transition $Z\to J/\psi + \gamma^{*}$ followed…

We present an analysis of the $e^+ e^- \to \gamma^* \to J/\psi \, \pi \, \pi \, (K \bar{K})$ and $e^+ e^- \to \gamma^* \to h_c \, \pi \, \pi$ processes employing the recently proposed Dalitz-plot decomposition approach, which is based on…