Related papers: A model to explain angular distributions of $J/\ps…

The CP asymmetry predicted by the Standard Model in the decay modes Bs;d -> J/psi eta and Bs -> J/psi phi is very small, and the observation of a sizeable e ect would be a clear indication of new physics beyond the Standard Model. Contrary…

Based on 58 million J/Psi events collected with the BESII detector at the BEPC, the baryon pair processes J/Psi to $\Sigma^+ \bar{\Sigma}^-$ and J/Psi to $\Xi^0 \bar{\Xi}^0$ are observed for the first time. The branching fractions are…

From $1310.6\times10^{6}$ $J/\psi$ and $448.1\times10^{6}$ $\psi(3686)$ events collected with the BESIII experiment, we report the first observation of $\Sigma^{+}$ and $\bar{\Sigma}^{-}$ spin polarization in $e^+e^-\rightarrow J/\psi…

Based on a sample of $58\times10^6J/\psi$ decays collected with the BESII detector at the BEPC, the $\bar\Lambda$ decay parameter $\alpha_{\bar\Lambda}$ for $\bar\Lambda\to \bar p \pi^+$ is measured using about 9000…

Using J/psi -> mu^+ mu^- decays from a sample of approximately 4 million psi(2S) events collected with the BESI detector, the branching fractions of psi(2S) -> eta J/psi, pi^0 pi^0 J/psi, and anything J/psi normalized to that of psi(2S) ->…

The decays $\chi_{cJ}\to\Sigma^{0}\bar{p}K^{+}+{\rm c.c.}~(J = 0, 1, 2)$ are studied via the radiative transition $\psi(3686)\to\gamma\chi_{cJ}$ based on a data sample of $(448.1 \pm 2.9)\times10^{6}$ $\psi(3686)$ events collected with the…

The nonleptonic two-body $\Lambda_b\rightarrow \Lambda\psi $ decays with $\psi=J/\psi$ or $\psi(2S)$ are investigated based on the perturbative QCD approach. These are color-suppressed processes in which the nonfactorizable contributions…

We introduce a set of observables representing angular distribution asymmetries, which can be viewed as a generalization of the forward-backward asymmetry of angular distributions, and can be used as an effective tool to search for $C\!P$…

By analyzing $(448.1\pm2.9)\times10^6$ $\psi(3686)$ events collected with the BESIII detector operating at the BEPCII collider, the decays of $\chi_{cJ} \to 4K_S^0$ ($J=0,1,2$) are observed for the first time with statistical significances…

Recently, the CMS and ATLAS collaborations have reported their $J/\psi J/\psi $ and $J/\psi \psi^\prime$ invariant mass distributions, respectively, for searching for fully charmed tetraquarks. Both of them reported the existence of a peak…

We derive the four-fold angular distribution for the semileptonic decay $\bar{B}\to D_2^*(\to D \pi)\,\ell \bar{\nu}$ where $D_2^*$(2460) is a tensor meson. We start with the most general beyond the Standard Model (SM) dimension-six…

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…

Motivated by the possible discrepancy between the observed CP asymmetry and that of standard model expectation in the decay mode B^0 -> phi K_S, we study the corresponding vector vector decay mode B^0 -> phi K^*. In order to obtain decisive…

The performance of the method of angular moments on the $\Delta\Gamma_s$ determination from analysis of untagged decays $B^0_s(t),\bar{B}^0_s(t)\to J/\psi (\to l^+l^-) \phi (\to K^+K^-)$ is examined by using the SIMUB generator. The results…

Cross-section distributions are calculated for the reaction $e^+ e^- \rightarrow J/\psi\rightarrow \bar{\Lambda}(\rightarrow \bar{p}\pi^+) \Lambda(\rightarrow p\pi^-)$, and related annihilation reactions mediated by vector mesons. The…

We construct an analytical model for two channel, two-body scattering amplitudes, and then apply it in the description of the three-body $J/\psi \to K^+K^-\pi^0$ decay. In the construction of the partial wave amplitudes, we combine the low…

A study of the angular distributions of the processes $\Lambda_b \to {\Lambda} V(1^-)$ with $V ({J/\Psi,\rho}^0)$ is performed. Emphasis is put on the initial $\Lambda_b$ polarization and the polarization density-matrices are derived to…

Based on $(27.12\pm 0.14)\times 10^{8}$ $\psi(2S)$ events collected with the BESIII detector, we search for the decay $\eta_c (2S) \rightarrow \pi^{+} \pi^{-} \eta_c$ with $\eta_c\rightarrow K_S^0 K^{\pm}\pi^{\mp}$ and $\eta_c\rightarrow…

Using a data sample of $4.481\times 10^8 \psi^\prime$ events collected with the BESIII detector, we report the first observation of the four-lepton-decays $J/\psi\to e^+e^-e^+e^-$ and $J/\psi\to e^+e^-\mu^+\mu^-$ utilizing the process…

We report measurements of branching fractions for psi(2S) decays into omega pi pi, b1 pi,omega f2(1270),omega KK, omega p pbar, phi pi pi, phi f0(980),phi KK, and an upper limit for phi p pbar final states based on a data sample of 4 X 10^6…