相关论文: Isospin violating decays of vector charmonia

Under the aegis of isospin conservation, the amplitudes in Born approximation, i.e., considering the only one-photon-exchange mechanism, of the decay $\psi\to \Lambda \overline \Sigma{}^0+{\rm c.c.}$, where $\psi$ is a vector charmonium,…

Using a sample of $(225.2\pm 2.8)\times 10^6$ $J/\psi$ events collected with the BESIII detector, we present results of a study of $J/\psi\rightarrow \gamma\Lambda\bar{\Lambda}$ and report the first observation of the isospin violating…

We analyse the two purely isospin-violating decays $\Lambda_b\rightarrow \Sigma^0 \phi$ and $\Lambda_b\rightarrow \Sigma^0 J/\psi$, proceed merely via the exchange topologies, in the framework of perturbative QCD approach. Assuming…

Based on $4.481\times10^8$ $\psi(3686)$ events collected with the BESIII detector at BEPCII, the branching fraction of the isospin violating decay $\psi(3686)\rightarrow\bar{\Sigma}^{0}\Lambda+c.c.$ is measured to be $(1.60 \pm 0.31 \pm…

Using a sample of $(2712.4\pm14.3)\times10^{6}$~$\psi(3686)$ events collected with the BESIII detector, we perform a search for the isospin-violating decays $\chi_{cJ}\to\Lambda\bar{\Sigma}^{0}+c.c.~(J=0,1,2)$ and…

Using a data sample of $(448.1\pm2.9)\times 10^6~\psi(3686)$ events collected with the BESIII detector at the BEPCII collider, we present measurements of branching fractions for the decays $\chi_{cJ} \rightarrow \Sigma^+ \bar{\Sigma}^-$ and…

Based on a sample of $448.1\times10^6\ \psi(3686)$ events collected with the BESIII detector, a study of $\psi(3686)\to\Lambda\bar{\Lambda}\pi^0$ and $\psi(3686)\to\Lambda\bar{\Lambda}\eta$ is performed. Evidence of the isospin-violating…

We present measurements of CP-violating asymmetries and branching fractions for the decays omegapi+, omegaK+, and omegaK0. The data sample corresponds to 232 million BBbar pairs produced by e+e- annihilation at the Upsilon(4S) resonance.…

Using $(27.12\pm 0.14)\times10^{8}$ $\psi(3686)$ events collected with the BESIII detector, we present the first observation of the decays $\chi_{cJ}\to\Lambda\bar{\Lambda}\omega$, where $J=0, 1, 2$, with statistical significances of $11.7…

In the presence of photons, the neutral $K_{\ell 4}$ decay, $K^0\to\pi^0\pi^-\ell^+\nu_\ell$, can be parameterized in terms of three vectorial, one anomalous, and one tensorial form factors. We present here analytic expressions of two…

We study CP violation in fermion pair decays of neutral boson particles with spin 0 or 1. We study a new asymmetry to measure CP violation in $\eta, K_L \rightarrow \mu^+\mu^-$ decays and discuss the possibility of measuring it…

In a model of isospin symmetry breaking we obtain the ($e^{-} e^{+} \rightarrow \pi^{-} \pi^{+}$) amplitude $Q$ and the isospin $I=0$ and $I=1$ relative phase $\psi$ at the $\phi (1020)$ resonance in aproximate agreement with experiment.…

Using 58 million $J/\psi$ and 14 million $\psi(2S)$ events collected by the BESII detector at the BEPC, branching fractions or upper limits for the decays $J/\psi$ and $\psi(2S) \to \Lambda \bar{\Lambda}\pi^0$ and $\Lambda…

Using $(10\,087 \pm 44) \times 10^6$ $J/\psi$ events collected with the BESIII detector, we perform the first amplitude analysis of the process $J/\psi\to\gamma\eta\pi^0$. The decay is dominated by the intermediate processes $J/\psi\to\pi^0…

Based on $(2712.4 \pm 14.3) \times 10^{6}$ $ e^{+}e^{-}\to\psi(3686)$ events collected with the BESIII detector operating at the BEPCII collider, we report the first evidence of $\chi_{c0}\to \Lambda\bar \Lambda \phi$ decays and the first…

Assuming isospin conservation, the decay of a $c\bar c$ vector meson into the $\Lambda\bar\Sigma^0+\mathrm{c.c.}$ final state is purely electromagnetic. At the leading order, the $c\bar c$ vector meson first converts into a virtual photon…

Based on a data sample of $(10087\pm44)\times10^6$ $J/\psi$ events collected with the BESIII detector, the branching fraction of $J/\psi\rightarrow\bar{\Lambda}\pi^{+}\Sigma^{-}+c.c.$ is measured to be $(1.221\pm 0.002\pm…

Decays of $\chi_{c1}$ to vector meson pairs $\phi\phi$, $\omega\omega$ and $\omega\phi$ are observed for the first time using $(106\pm4)\times 10^6$ $\psip$ events accumulated at the BESIII detector at the BEPCII $e^+e^-$ collider. The…

The first observation of the decays $J\!/\!\psi \rightarrow \bar{p} \Sigma^{+} K_{S}^{0}$ and $J\!/\!\psi \rightarrow p \bar{\Sigma}^{-} K_{S}^{0}$ is reported using $(10087\pm44)\times10^{6}$ $J\!/\!\psi$ events recorded by the BESIII…

We report on a study of the isospin-violating and conserving decays of the J/psi and psi(2S) charmonium state to Lambda Lambdabar pi0 and Lambda Lambdabar eta, respectively. The data are based on 225 million J/psi and 106 million psi(2S)…