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The study of hyperon decays at the Beijing Electron Spectrometer III (BESIII) is proposed to investigate the events of $J/\psi$ decay into hyperon pairs, which provide a pristine experimental environment at the Beijing Electron--Positron Collider II. About $10^{6}$--$10^8$ hyperons, i.e., $\Lambda$, $\Sigma$, $\Xi$, and $\Omega$, will be produced in the $J/\psi$ and $\psi(2S)$ decays with the proposed data samples at BESIII. Based on these samples, the measurement sensitivity of the branching fractions of the hyperon decays is in the range of $10^{-5}$--$10^{-8}$. In addition, with the known center-of-mass energy and "tag technique," rare decays and decays with invisible final states can be probed., Comment: 8 pages, 8 tables, add more references and corrections; many typos fixed; erratum added: https://doi.org/10.1007/s11467-019-0910-7

In blind motion deblurring, leading methods today tend towards highly non-convex approximations of the l0-norm, especially in the image regularization term. In this paper, we propose a simple, effective and fast approach for the estimation of the motion blur-kernel, through a bi-l0-l2-norm regularization imposed on both the intermediate sharp image and the blur-kernel. Compared with existing methods, the proposed regularization is shown to be more effective and robust, leading to a more accurate motion blur-kernel and a better final restored image. A fast numerical scheme is deployed for alternatingly computing the sharp image and the blur-kernel, by coupling the operator splitting and augmented Lagrangian methods. Experimental results on both a benchmark image dataset and real-world motion blurred images show that the proposed approach is highly competitive with state-of-the- art methods in both deblurring effectiveness and computational efficiency., Comment: 32 pages, 16 figures

The lepton number violating process can be induced by introducing a fourth generation heavy Majorana neutrino, which is coupled to the charged leptons of Standard Model. There have been many previous studies on the leptonic number violating decay processes with this mechanism, we follow the trend to study the process: $D \to K \ell \ell \pi$ with the same-sign dilepton final states. We restrict ourself to certain neutrino mass regions, in which the heavy neutrino could be on shell and the dominant contribution to the branching fraction comes from the resonance enhanced effect. Applying the Narrow Width Approximation, we found that upper limit for the branching fractions for $D^0 \to K^-\ell^+\ell^+\pi^-$ are generally at the order of $10^{-10}$ to $10^{-9}$, if we take the most stringent upper limit bound currently available in the literature for the mixing matrix elements. We also provide the constrains, which is competitive compared to the LNV B decays, on the mixing matrix element $|V_{eN}|^2$ based on the upper limit of $D^0 \to K^- e^+ e^+ \pi^-$ estimated from Monte-Carlo study at BESIII., Comment: 17 pages, 3 figures, 5 tables, references added and numerical results updated

About 2.9 fb$^{-1}$ data set had been collected with the BESIII detector at the BEPCII collider. Taking advantages of data near open-charm threshold, we present preliminary results on leptonic and semileptonic charm-meson decays, as well as result on the FCNC process $D^0 \rightarrow \gamma \gamma$ from BESIII experiment. High precision charm data will enable us to validate Lattice QCD calculations at the few percent level. These can then be used to make precise measurements of CKM elements, $V_{cd}$ and $V_{cs}$, which are useful to improve the accuracy of test of the CKM unitary., Comment: 7 pages, 9 figures, proceedings for talk at BEACH 2012, July 23-28, 2012 in Wichita, USA

Hadron physics represents the study of strongly interacting matter in all its manifestations and the understanding of its properties and interactions. The interest on this field has been revitalized by the discovery of new light hadrons, charmonium- and bottomonium-like states. I review the most recent experimental results from different experiments., Comment: Presented at Lepton-Photon 2011, Mumbai, India; 21 pages, 18 figures; add more references; some correction

Recently, LHCb experiment announced a 3.5$\sigma$ evidence for direct CP violation in $D^0$ decay by looking at the difference between $A_{CP}(D^0\rightarrow K^+K^-)$ and $A_{CP}(D^0\rightarrow \pi^+\pi^-)$. This is the first evidence of CP violation in charm system, which may indicate new physics beyond the Standard Model. Motivated by this measurement, we review rare processes in charmonium decay, especially, the weak decay, $C$ or $P$ violated decay and lepton flavor violated decays. In case the new physics appears in charm sector, these rare decays of charmonium states will provide opportunity to search for significant contributions from physics beyond the Standard Model. With huge $J/\psi$ and $\psi(2S)$ samples in BESIII experiment, the rare decays may be feasible., Comment: 9 pages, Submitted to Chinese Physics C. arXiv admin note: text overlap with arXiv:0710.0039 by other authors

We study the electromagnetic Dalitz decay modes of $J/\psi \rightarrow P l^+l^-$ ($P= \pi^0$, $\eta$ or $\eta^\prime$). In these decays, the lepton pairs are formed by internal conversion of an intermediate virtual photon with invariant mass $m_{l^+l^-}$. Study of the effective-mass spectrum of the $l^+l^-$ will shed light on the dynamic transition form factor $F_{J/\psi P}(q^2)$ ($q^2 = m^2_{l^+l^-}$), which characterizes the electromagnetic structure arising at the vertex of the transition $J/\psi$ to pseudoscalars. We also discuss the direct productions of a GeV scale vector $U$ boson in these processes $J/\psi \rightarrow PU$ ($U\rightarrow l^+l^-$). It is responsible for mediating a new $U(1)_d$ interaction, as recently exploited in the context of weakly interacting massive particle dark matter. In this paper, we firstly use the usual pole approximation for the form factor to estimate the decay rate of $J/\psi \rightarrow P l^+l^-$ in the standard model. Then the reach of searching for the dark photon is estimated. We suggest that these Dalitz decays can be used to search for the light $U$ boson in the BESIII experiment with a huge $J/\psi$ data set., Comment: 6 pages, 3 figure, add two more figures, more discussions