相关论文: Anomalous enhancement of the isospin-violating $\L…
Among the light baryons, the $J^\pi = \frac{1}{2}^-$ $\Lambda(1405)$ hyperon is an important special case as it sits just below the $N\bar{K}$ threshold and decays almost exclusively to $\Sigma\pi$. Some long-standing hypotheses for…
The mechanism for the formation of the $\Lambda(1405)$ resonance is studied in a chiral quark model that includes quark-meson as well as contact (four point) interactions. The negative-parity $S$-wave scattering amplitudes for strangeness…
The BESIII Collaboration recently reported the observation of the $a_0(980)^0-f_0(980)$ mixing in the isospin breaking decay $J/\psi\to \eta\pi^0\phi$. In the Dalitz plot for that decay with the $\eta$ reconstructed from two photons, there…
Using $e^+e^-\to\Lambda_c^+\bar\Lambda_c^-$ production from a 567 pb$^{-1}$ data sample collected by BESIII at 4.6 GeV, a full angular analysis is carried out simultaneously on the four decay modes of $\Lambda_c^+\to pK_S^0$, $\Lambda…
Since the discovery of the $\Lambda(1405)$, it remains poorly described by conventional constituent quark models, and it is a candidate for having an "exotic" meson-baryon or "penta-quark" structure, similar to states recently reported in…
The $K^- d \to \pi YN$reaction is theoretically studied so as to investigate the $K^{-}$-induced production of the hyperon resonances $\Sigma (1385)$ and $\Lambda (1405)$. For this purpose we take into account the p-wave amplitudes for the…
The K^- induced production of Lambda(1405) is investigated in K^- d to pi Sigma n reactions based on coupled-channels chiral dynamics, in order to discuss the resonance position of the Lambda(1405) in the KbarN channel. We find that the…
The properties of the $\Lambda(1405)$ resonance have been investigated from radiative decay of $K^- p\to Y\gamma$ and photoproduction $\gamma p\to K^+\Lambda(1405)$ within the framework of the isobar model. For a consistent result with…
$Z_c(4430)$ discovered in $\bar{B}^0\to\psi(2S)K^-\pi^+$, $Z_c(4200)$ found in $\bar{B}^0\to J/\psi K^-\pi^+$, and $Z_1(4050)$ and $Z_2(4250)$ observed in $\bar{B}^0\to\chi_{c1}K^-\pi^+$ are candidates of charged charmonium-like states. All…
In this paper, we study the polarization of the $\Lambda(1405)$ in the $\gamma p \rightarrow K^+ \pi \Sigma$ reaction within an effective Lagrangian approach and isobar model. In our model, the $\Lambda(1405)$ is excited through the…
We analyze the decay B0-->K+ pi- pi0 with a sample of 454 million B Bbar events collected by the BaBar detector at the PEP-II asymmetric-energy B factory at SLAC, and extract the complex amplitudes of seven interfering resonances over the…
The $\gamma p \to K^+ \pi^0 \Lambda$ and $\gamma p \to K^+ \pi \Sigma $ reactions are studied in the kinematic region where the $\pi^0 \Lambda$(1116) and $\pi\Sigma$(1192) pairs originate dominantly from the decay of the $\Sigma$(1385) and…
Recently we presented a successful strategy to extract the position of the two $\Lambda(1405)$ poles from experimental photoproduction data on the $\gamma p \to K^+ \pi^0 \Sigma^0 $ reaction at Jefferson Lab. Following a similar strategy,…
We present preliminary results of improved measurements of the CP-violating asymmetries and branching fractions in the decays B0 -> pi+ pi-, B0 -> K+ pi-, B0 -> pi0 pi0, and B0 -> K0 pi0. This update includes all data taken at the Y(4S)…
The total and differential cross sections for associated strangeness production in the $pp \to pK^+K^-p$ and $pp \to pK^+\pi^0\Sigma^0$ reactions have been studied in a unified approach using an effective Lagrangian model. It is assumed…
Based on 4.5 fb$^{-1}$ of $e^{+}e^{-}$ collision data accumulated at center-of-mass energies between $4599.53$ MeV and $4698.82$ MeV with the BESIII detector, the decay $\Lambda_{c}^{+}\to nK_{S}^{0}\pi^+\pi^0$ is observed for the first…
The electroproduction of $K^+ \Lambda$ (1405) was studied by analyzing the E1F data set collected in Hall B at Jefferson Lab. The analysis utilized the decay channel $\Sigma^+ \pi^-$ of the $\Lambda$ (1405) and $p \pi^0$ of the $\Sigma^+$.…
The radiative decay of $\Lambda (1405)$ is investigated from the viewpoint of compositeness, which corresponds to the amount of two-body states composing resonances as well as bound states. For a $\bar{K}N (I=0)$ bound state without…
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 show the important role played by the $\pi\Delta(1232)$ channel in the build up of the $N(1700)(3/2^-)$ resonance due to the non-trivial enhancement produced by a singularity of a triangular loop. The $N(1700)$ is one of the dynamically…