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The spin density matrix of the $omega$ has been determined for the reaction $bar{p} p , rightarrow , omega pi^0$ with unpolarized in-flight data measured by the Crystal Barrel LEAR experiment at CERN. The two main decay modes of the $omega$ into $pi^0 gamma $ and $pi^+ pi^- pi^0$ have been separately analyzed for various $bar{p}$ momenta between 600 and 1940 MeV/c. The results obtained with the usual method by extracting the matrix elements via the $omega$ decay angular distributions and with the more sophisticated method via a full partial wave analysis are in good agreement. A strong spin alignment of the $omega$ is clearly visible in this energy regime and all individual spin density matrix elements exhibit an oscillatory dependence on the production angle. In addition, the largest contributing orbital angular momentum of the $bar{p}p$ system has been identified for the different beam momenta. It increases from $L^{max}_{bar{p}p}$ = 2 at 600 MeV/c to $L^{max}_{bar{p}p}$ = 5 at 1940 MeV/c.
The decay $J/psi rightarrow omega p bar{p}$ has been studied, using $225.3times 10^{6}$ $J/psi$ events accumulated at BESIII. No significant enhancement near the $pbar{p}$ invariant-mass threshold (denoted as $X(pbar{p})$) is observed. The upper limi
The s-channel annihilation of proton and antiproton into a neutral pion and a real or virtual photon followed by lepton pair emission is studied. Such mechanism is expected to play a role at moderate values of the total energy $sqrt{s}$, when the pio
Using a low-background sample of $2.6times 10^5$ $J/psirightarrowomegaeta(omegarightarrowpi^{+}pi^{-}pi^{0},etarightarrowgammagamma)$ events, about 5 times larger statistics than previous experiments, we present a Dalitz plot analysis of the decay $o
The decay $J/psi to omega p bar p$ is studied using a $5.8 times 10^7$ $J/psi$ event sample accumulated with the BES II detector at the Beijing electron-positron collider. The decay branching fraction is measured to be $B(J/psi to omega p bar p)=(9.8
The most recent high-precision data on spin observables $Sigma$, $T$, $P$, $E$, $F$ and $H$ reported by the CLAS Collaboration together with the previous data on differential cross sections and spin-density-matrix elements reported by the CLAS, A2, G