Related papers: Non-strange light-meson spectroscopy at COMPASS

Despite decades of research, we still lack a detailed quantitative understanding of the way quantum chromodynamics (QCD) generates the spectrum of hadrons. Precise experimental studies of the hadron excitation spectrum and the dynamics of…

Results are presented on J/psi radiative decays to pi^+pi^- and pi^0pi^0 based on a sample of 58M J/psi events taken with the BESII detector. Partial wave analyses are carried out using the relativistic covariant tensor amplitude method in…

We study the spin-exotic $J^{PC} = 1^{-+}$ amplitude in single-diffractive dissociation of 190 GeV$/c$ pions into $\pi^-\pi^-\pi^+$ using a hydrogen target and confirm the $\pi_1(1600) \to \rho(770) \pi$ amplitude, which interferes with a…

In order to study diffractive dissociation reactions, COMPASS has taken data with a 190 GeV/$c$ pion beam impinging on a liquid hydrogen target in 2008 and 2009. At squared four-momentum transfers to the target t' between 0.1 GeV$^2/c^2$…

We investigate the hybrid exotic meson with $J^{PC}=1^{-+}$ within the framework of an AdS/QCD model. Introducing a holographic field dual to the operator for hybrid exotic meson, we obtain the eigen-value equation for its mass. Fixing all…

The first full amplitude analysis of $B^+\to J/\psi \phi K^+$ with $J/\psi\to\mu^+\mu^-$, $\phi\to K^+K^-$ decays is performed with a data sample of 3 fb$^{-1}$ of $pp$ collision data collected at $\sqrt{s}=7$ and $8$ TeV with the LHCb…

The resonant structure of the reaction $\overline{B}^0\rightarrow J/\psi \pi^+\pi^-$ is studied using data from 3 fb$^{-1}$ of integrated luminosity collected by the LHCb experiment, one-third at 7 Tev center-of-mass energy and the…

Based on a sample of $(2712.4\pm14.3)\times10^6\;\psi(3686)$ events collected with the BESIII detector, a partial wave analysis of the decay $\psi(3686)\to\Lambda\bar\Sigma^0\pi^0+c.c.$ is performed to investigate $\Lambda^*$ and $\Sigma^*$…

The search for mesons with non-quark-antiquark (exotic) quantum numbers has gone on for nearly thirty years. There currently is experimental evidence of three isospin one states, the $\pi_{1}(1400)$, the $\pi_{1}(1600)$ and the…

An amplitude analysis of $B^-\to J/\psi\Lambda\bar{p}$ decays is performed using about 4400 signal candidates selected on a data sample of $pp$ collisions recorded at center-of-mass energies of 7, 8 and 13 TeV with the LHCb detector,…

We report on analyses of $B^-$ mesons decaying into $D^{*+}\pi^-\pi^-$ and $D^+\pi^-\pi^-$ final states using 89 million $B^-$ decays collected by the BABAR detector at the PEP-II asymmetric-energy $B$ Factory. Preliminary measurements are…

We present the first lattice QCD calculation of coupled $\pi\omega$ and $\pi\phi$ scattering, incorporating coupled $S$ and $D$-wave $\pi\omega$ in $J^P=1^+$. Finite-volume spectra in three volumes are determined via a variational analysis…

Using $pp$ collision data corresponding to an integrated luminosity of $5.4\,{\rm fb}^{-1}$ collected with the LHCb detector at a center-of-mass energy of $13\,{\rm TeV}$, the $B^0\to D^-D^+K^+\pi^-$ decay is studied. A new excited $D_s^+$…

We use a combination of quark-antiquark and $B^{(*)}K$ interpolating fields to predict the mass of two QCD bound states below the $B^*K$ threshold in the quantum channels $J^P=0^+$ and $1^+$. The mesons correspond to the b-quark cousins of…

The first observation of the rare decay$B^0_s \to \phi\pi^+\pi^-$ and evidence for $B^0 \to \phi\pi^+\pi^-$ are reported, using $pp$ collision data recorded by the LHCb detector at centre-of-mass energies $\sqrt{s} = 7$ and 8~TeV,…

COMPASS is a fixed-target experiment at the CERN SPS which focused on light-quark hadron spectroscopy during the data taking periods in 2008 and 2009. A world-leading data set was collected with a 190GeV/c hadron beam impinging on a liquid…

Utilizing the approach recently proposed for the inclusive semi-leptonic decay rate on the lattice, we compute the differential decay rate of a $B_s$ meson for various kinematical channels. The results are compared with the contributions…

A decay width calculation for a hybrid exotic meson h, with JPC=1-+, is presented for the channel h->pi+a1. This quenched lattice QCD simulation employs Luescher's finite box method. Operators coupling to the h and pi+a1 states are used at…

The newly reported exotic signal $Z_c(4100)$ by the LHCb Collaboration in the invariant mass spectrum of $\eta_c\pi^-$ in $B^0\to \eta_c K^+ \pi^-$ has been a new experimental evidence for an exotic meson containing four constituent quarks.…

We discuss a coupled channel analysis of the $\eta\pi$ and $\eta'\pi$ systems produced in $\pi^-p$ interactions at 18 GeV/$c$. We show that known $Q\bar Q$ resonances, together with residual soft meson-meson rescattering, saturate the…