Related papers: Precision Meson Spectroscopy at COMPASS
Beam-recoil transferred polarizations for the exclusive $\vec{e}p \to e'K^+ \vec{\Lambda},\vec{\Sigma}^0$ reactions have been measured using the CLAS spectrometer at Jefferson Laboratory. New measurements have been completed at beam…
We study the processes $e^+e^-\to 2(\pi^+\pi^-)\pi^0\pi^0\pi^0\gamma$ and $2(\pi^+\pi^-)\pi^0\pi^0\eta\gamma$ in which an energetic photon is radiated from the initial state. The data were collected with the \babar~ detector at SLAC. About…
The electroexcitation amplitudes or $\gamma_vpN^*$ electrocouplings of the $N(1440)1/2^+$, $N(1520)3/2^-$, and $\Delta(1600)3/2^+$ resonances were obtained for the first time from the $ep \to e'\pi^+\pi^-p'$ differential cross sections…
The resonance-like signal with axial-vector quantum numbers $J^{PC}=1^{++}$ at a mass of $1420\,$MeV and a width of $140\,$MeV, recently observed by the COMPASS and VES experiments in the $f_0(980)\pi$ final state and tentatively called…
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 study the processes $e^+e^-\to\pi^+\pi^-\pi^0\pi^0\pi^0\gamma$ and $\pi^+\pi^-\pi^0\pi^0\eta\gamma$ in which an energetic photon is radiated from the initial state. The data were collected with the BaBar~ detector at SLAC. About 14\,000…
We present an analysis of the Lambda(1405) resonance in p+p reactions at a kinetic beam energy of 3.5 GeV, measured by the High Acceptance Di-Electron Spectrometer (HADES). The resonance is reconstructed in the two charged decay channels…
We study the process $e^+e^- \to \pi^+\pi^-\eta \gamma$, where the photon is radiated from the initial state. About 8000 fully reconstructed events of this process are selected from the BaBar data sample with an integrated luminosity of…
The experimental data from 2m propane bubble chamber have been analyzed to search of scalar meson $\kappa$(800) in $K^0_s\pi^{\pm}$ spectra for the reaction p+A at 10 GeV/c. The $K^0_s\pi^{\pm}$ invariant mass spectra has shown similarly…
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…
Exclusive and kinematically complete high-statistics measurements of the double pionic fusion reaction $dd \to ^4$He$\pi^0\pi^0$ have been performed in the energy range 0.8 - 1.4 GeV covering thus the region of the ABC effect, which denotes…
A sample of 35,000 events of the type pi-p --> eta'pi-p_slow (eta' --> eta pi-pi+, eta --> gamma gamma) with -t>0.1 GeV^2/c^2 was selected from COMPASS 2008 data for a partial-wave analysis. We study the broad P_+ structure known from…
The production cross sections of fragmentation-evaporation residues in the reaction Pb+p at 500A MeV have been measured using the inverse-kinematics method and the FRS spectrometer (GSI). Fragments were identified in nuclear charge using…
We consider the first pion excitation as a sub-continuum resonance in the pseudoscalar channel, and we obtain parameters characterizing this resonance through a global fit of the Borel-parameter dependence of the field-theoretical…
Interpretation of CP violation measurements using charmonium decays, in both the B0 and Bs systems, can be subject to changes due to "penguin" type diagrams. These effects can be investigated using measurements of the Cabibbo-suppressed…
We calculate the parameters describing elastic $I=1$, $P$-wave $\pi\pi$ scattering using lattice QCD with $2+1$ flavors of clover fermions. Our calculation is performed with a pion mass of $m_\pi \approx 320\:\:{\rm MeV}$ and a lattice size…
COMPASS is a multi-purpose fixed-target experiment at CERN's M2 beam line aimed at studying the structure and spectrum of hadrons. It has collected the so far world's largest data set on diffractive production of the $K^-\pi^-\pi^+$ final…
CERN COMPASS plans measurements of gamma-pi and gamma-K interactions using 50-280 GeV pion (kaon) beams and a virtual photon target. Pion (kaon) polarizabilities and radiative transitions will be measured via Primakoff effect reactions such…
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,…
Exclusive measurements of the p p -> p p pi+ pi- reaction have been carried out at Tp = 775 MeV at CELSIUS using the PROMICE/WASA setup. Together with data obtained at lower energy they point to a dominance of the Roper excitation in this…