相关论文: $ \omega (\to \pi^+\pi^-\pi^0) $ meson photoproduc…
We study the reaction mechanism for the correlated $\pi^0\gamma$ emission in the photon induced reaction on the proton target. Since this reaction is studied in the GeV region, we assume that it proceeds through the formation of the vector…
The exclusive reaction $\gamma p \to p \pi^+ \pi^-$ was studied in the photon energy range 3.0 - 3.8 GeV and momentum transfer range $0.4<-t<1.0$ GeV$^2$. Data were collected with the CLAS detector at the Thomas Jefferson National…
The differential cross sections and unpolarized spin-density matrix elements for the reaction $\gamma p\to p\omega$ were measured using the CBELSA/TAPS experiment for initial photon energies ranging from the reaction threshold to 2.5 GeV.…
The $\rho^0-\omega$ interference has been studied in the dilepton invariant mass distribution spectra in the photonuclear reaction, but that is not done for the gamma-nucleon reaction. Recent past, the $e^+e^-$ invariant mass distribution…
The exclusive production cross sections for $\omega$ and $\phi$ mesons have been measured in proton-proton reactions at $p_{lab}=3.67$ GeV/c. The observed $\phi/\omega$ cross section ratio is $(3.8\pm0.2^{+1.2}_{-0.9})\times 10^{-3}$. After…
The differential cross section, $d\sigma/dt$ for $\omega$ meson exclusive photoproduction on the proton above the resonance region ($2.6<W<2.9$ GeV) was measured up to a momentum transfer $-t = 5$ GeV$^2$ using the CLAS detector at…
Differential cross sections for the reaction $\gamma p \to n \pi^+$ have been measured with the CEBAF Large Acceptance Spectrometer (CLAS) and a tagged photon beam with energies from 0.725 to 2.875 GeV. Where available, the results obtained…
An experimental study of $\omega$ photoproduction on the proton was conducted by using the Crystal Ball and TAPS multiphoton spectrometers together with the photon tagging facility at the Mainz Microtron MAMI. The $\gamma p\to\omega p$…
We have measured the differential cross section for the gamma n --> pi- p and gamma p --> pi+ n reactions at center of mass angle of 90 degree in the photon energy range from 1.1 to 5.5 GeV at Jefferson Lab (JLab). The data at photon…
Exclusive photoproduction of $\rho^0(770)$ mesons is studied using the H1 detector at the $ep$ collider HERA. A sample of about 900000 events is used to measure single- and double-differential cross sections for the reaction $\gamma p \to…
We report on a study of the reaction, $\gamma p \to p \pi^+\pi^+\pi^-\pi^-\pi^0$, at an incident photon energy of 19.3 GeV. The most significant feature of this reaction is $\Delta^{++}$ production which occurs with a cross section of…
The differential cross section for the reaction p(gamma, eta p) has been measured from threshold to 1100 MeV photon laboratory energy. For the first time, the region of the S11(1535) resonance is fully covered in a photoproduction…
Photoproduction of pi0 mesons was studied with the Crystal-Barrel detector at ELSA for incident energies from 300 MeV to 3 GeV. Differential cross sections d sigma /d Omega, d sigma/d t, and the total cross section are presented. For…
First we calculate cross section for the $\gamma p \to \omega p$ reaction from the threshold to very large energies. At low energies the pion exchange is the dominant mechanism. At large energies the experimental cross section can be well…
The reaction $\gamma p \rightarrow \omega p$ $(\omega \rightarrow \pi^+\pi^-\pi^0$ and $\pi^0\rightarrow\gamma\gamma)$ has been studied in $ep$ interactions using the ZEUS detector at photon-proton centre-of-mass energies between $70$ and…
The $\omega$-meson photoproduction, $\gamma+p\to p+\omega$, is studied in the framework of a model, containing $\pi$-meson exchange in t-channel and nucleon-exchange in s- and u-channels. Considering both $\omega NN$-coupling constants in…
We investigate the discovery potential of the $a_1(1260)$ photoproduction in the $\gamma p \to a_1(1260)^+ n$ and $\gamma p \to \pi^+\pi^+\pi^- n$ reactions via the $\pi$-exchange mechanism. For the $\gamma p \to \pi^+\pi^+\pi^- n$…
Photoproduction cross sections are reported for the reaction $\gamma p\to p\eta$ using energy-tagged photons and the CLAS spectrometer at Jefferson Laboratory. The $\eta$ mesons are detected in their dominant charged decay mode, $\eta\to…
Differential cross sections at $t=t_{\text{min}}$ and decay asymmetries for the $\gamma p\rightarrow\phi p$ reaction have been measured using linearly polarized photons in the range 1.5 to 2.9 GeV. These cross sections were used to…
The differential cross section for the gamma +n --> pi- + p and the gamma + p --> pi+ n processes were measured at Jefferson Lab. The photon energies ranged from 1.1 to 5.5 GeV, corresponding to center-of-mass energies from 1.7 to 3.4 GeV.…