Related papers: Proposal to detect a moving triangle singularity i…

We have searched for the decay $K^+ \to \pi^+ \nu \bar\nu$ in the kinematic region with pion momentum below the $K^+ \to \pi^+ \pi^0$ peak. One event was observed, consistent with the background estimate of $0.73\pm 0.18$. This implies an…

We study for the first time the $p\Sigma^-\to K^-d$ and $K^-d\to p\Sigma^-$ reactions close to threshold and show that they are driven by a triangle mechanism, with the $\Lambda(1405)$, a proton and a neutron as intermediate states, which…

Via the Initial Single Pion Emission (ISPE) mechanism, we study the $\phi(1020)\pi^{+}$ invariant mass spectrum distribution of $Y(2175) \to \phi(1020)\pi^{+} \pi^{-}$. Our calculation indicates there exist a sharp peak structure…

The invariant mass spectra of the $\pi^+\pi^-$ and $\pi^\pm\pi^0$ pairs in the process $e^+e^- \to \pi^+\pi^-\pi^0$ were studied in the SND experiment at the VEPP-2M collider in the energy region $\sqrt[]{s} \simeq 1020$ MeV. These studies…

We, using an effective Lagrangian approach, investigated the dipionic transition of the $Y(4500)$ newly well established in the process $e^+e^-\to K^+K^- J/\psi$. In this study, the $Y(4500)$ was considered as a mixture of the $\psi(5S)$…

Using data samples collected at sqrt(s) = 3.686GeV and 3.650GeV by the BESII detector at the BEPC, the branching fraction of psi(2S) -> 3(pi+pi-) is measured to be [4.83 +- 0.38(stat) +- 0.69(syst)] x 10^-4, and the relative branching…

We derive the vertices of five-meson and seven-meson anomaly processes from the four dimensional expansion form of Wess-Zumino term. Using these vertices we calculate the amplitude, both the finite part and divergent part, of {$K^+ K^-…

A search for violation of the charge-parity $C\!P$ symmetry in the $D^+\rightarrow K^-K^+\pi^+$ decay is presented, with proton-proton collision data corresponding to an integrated luminosity of 5.4 fb$^{-1}$, collected at a center-of-mass…

Using the data sample of 980 fb$^{-1}$ collected with the Belle detector operating at the KEKB asymmetric-energy $e^+e^-$ collider, we present the results of an investigation of the $\Lambda\pi^+$ and $\Lambda\pi^-$ invariant mass…

We describe a high-resolution spectroscopy method, in which the detection of single excitation events is enhanced by a complete loss of coherence of a superposition of two ground states. Thereby, transitions of a single isolated atom nearly…

The process $e^+e^-\to K^0_S K^0_S \psi(3686)$ is studied by analyzing $e^+e^-$ collision data samples collected at eight center-of-mass energies ranging from 4.682 to 4.951 GeV with the BESIII detector operating at the BEPCII collider,…

The decays $B^0_s \rightarrow J/\psi \pi^+\pi^- K^+ K^-$ are studied using a data set corresponding to an integrated luminosity of 9fb$^{-1}$, collected with the LHCb detector in proton-proton collisions at centre-of-mass energies of 7, 8…

It has been clear for past many years that in low energy observables new physics can only appear as a perturbation. Therefore precise theoretical predictions and precise experimental measurements have become mandatory. Here we draw…

The cross section of the process $e^+e^- \to 3(\pi^+\pi^-)$ has been measured using 22 pb$^{-1}$ of integrated luminosity collected with the CMD-3 detector at the VEPP-2000 $e^+e^-$ collider in the c.m. energy range 1.5 -- 2.0 GeV. The…

We report a study of the suppressed decays $B^- \to [K^+\pi^-]_D K^-$ and $B^- \to [K^+\pi^-]_D \pi^-$, where $[K^+\pi^-]_D$ indicates that the $K^+\pi^-$ pair originates from a neutral $D$ meson. These decay modes are sensitive to the…

We generalize our previous work on \pi\pi scattering to K\pi scattering, and re-analyze the experiment data of K\pi scattering below 1.6 GeV. Without any free parameter, we explain K\pi I=3/2 S-wave phase shift very well by using t-channel…

The first observation of the decay K^+ --> pi^+ gamma gamma is reported. A total of 31 events was observed with an estimated background of 5.1 +- 3.3 events in the pi+ momentum range from 100 MeV/c to 180 MeV/c. The corresponding partial…

We report the observation of a narrow charmonium-like state produced in the exclusive decay process B+ -> K+ pi+pi- J/psi. This state, which decays into pi+pi- J/psi, has a mass of 3872.0+-0.6(stat)+-0.5(syst) MeV, a value that is very near…

The decay $B_c^+ \to \psi(2S)\pi^+$ with $\psi(2S) \to \mu^+\mu^-$ is observed with a significance of $5.2\,\sigma$ using $pp$ collision data corresponding to an integrated luminosity of $1.0\,\invfb$ collected by the LHCb experiment. The…

The amplitudes of the $K^{\pm} \to 3\pi$ and $K \to 2\pi$ decays are expressed in terms of different combinations of one and the same set of CP-conserving and CP-odd parameters. Extracting the magnitudes of these parameters from the data on…