相关论文: Study of the reaction $\gamma p\to p\pi^0\eta$

High-quality cross sections for the reaction gamma+d->pi^0+d have been measured using the CLAS at Jefferson Lab over a wide energy range near and above the eta-meson photoproduction threshold. At backward c.m. angles for the outgoing pions,…

In this work, the role of the $\Delta ^{\ast }$ resonances in the process of $pp\rightarrow nK^{+}\Sigma ^{+}$ are systematically investigated with the effective Lagrangian approach and the isobar model. We find that a $P_{31}$ state,…

We report the measurement of the ratio $\Gamma(\eta \to \pi^+\pi^-\gamma)/\Gamma(\eta \to \pi^+\pi^-\pi^0)$ analyzing a large sample of $\phi \to \eta \gamma$ decays recorded with the KLOE experiment at the DA$\Phi$NE $e^+ e^-$ collider,…

Cross sections, beam asymmetries, and recoil polarisations for the reactions gamma p to K^+ Lambda ; gamma to K^+ Sigma^0, and gamma p to K^0 Sigma^+ have been measured by the SAPHIR, CLAS, and LEPS collaborations with high statistics and…

We present a phenomenological model for the $\gamma\gamma \to \pi^+\pi^-\pi^0$ reaction by including the production mechanism of the $a_2(1320)$ resonance, as well as the contributions from the $\sigma/f_0(500)\, \pi^0$ and $f_2(1270)\,…

We study the charmonium $p \bar{p} \to \psi(3770) \pi^0$ reaction using effective lagrangian approach where the contributions from well established $N^*$ states are considered, and all parameters are fixed in the process of $e^+e^- \to p…

A constituent quark model is developed for the reaction, allowing us to investigate all available data for differential cross sections as well as single polarization asymmetries (beam and target) by including {\it all} of the PDG, one to…

The decays of $N^*$ and $\Delta^*$ resonances into $N\rho$, $\Delta\pi$ and $N\sigma$ final states are studied in a coupled-channel analysis of data on pion- and photo-induced reactions. Improvements in the fit were observed when new…

We present a theoretical study of the $\gamma\gamma \to \pi\eta$ process from the threshold up to 1.4 GeV in the $\pi\eta$ invariant mass. For the s-wave $a_0(980)$ resonance state we adopt a dispersive formalism using a coupled-channel…

We have studied the $N^*(2120)$, $\Delta^*(1940)$, and the possible $\Sigma^*(1380)$ resonances in the $\gamma p \to K^+ \Lambda(1520)$, $pp \to n K^+ \Sigma(1385)$, and $\Lambda p \to \Lambda p \pi^0$ reactions within the resonance model…

Photoproduction of $\pi\eta$-pairs from nucleons has been investigated from threshold up to incident photon energies of $\approx$~1.4~GeV. The quasi-free reactions $\gamma p\rightarrow p\pi^0\eta$, $\gamma n\rightarrow n\pi^0\eta$, $\gamma…

The cross section of the $e^+e^-\to\omega\pi^0\to\pi^0\pi^0\gamma$ reaction was measured by the SND detector at VEPP-2M $e^+e^-$ collider in the energy range from threshold up to 1.4 GeV. Results of the cross section fitting by the sum of…

We present a unified picture which studies simultaneously the gamma gamma--> pi^+ pi^-, pi^0 pi^0,K^+ K^-, K^0 bar{K}^0, pi^0 eta reactions up to about sqrt(s)=1.4 GeV reproducing the experimental cross sections. The present work implements…

A combined analysis of the reactions $\pi^-p\rightarrow K^0\Lambda$ and $\eta n$ is carried out with a chiral quark model. The data in the center-of-mass (c.m.) energy range from threshold up to $W\simeq 1.8$ GeV are reasonably described.…

The nucleon resonances near 2 GeV are investigated through the $\Sigma$(1385) and $\Lambda(1520)$ photoproductions within a Regge-plus-resonance approach based on the new experimental data released by the CLAS Collaboration. The…

First exclusive data for the $pp \to nn\pi^+\pi^+$ reaction have been obtained at CELSIUS with the WASA detector setup at a beam energy of $T_p$ = 1.1 GeV. Total and differential cross sections disagree with theoretical calculations, which…

We investigate the two-body reaction $\pi^- p \to K^{0} \Lambda$ within the effective Lagrangian approach and the isobar model. In addition to the "background" contributions from $t$-channel $K^*$ exchange, $u$-channel $\Sigma(1192)$ and…

The $^{11}$C($\alpha$, p) reaction is an important $\alpha$-induced reaction competing with $\beta$-limited hydrogen-burning processes in high-temperature explosive stars. We directly measured its reaction cross sections both for the…

The dynamical model developed in [Phys. Rev. C 54, 2660 (1996)] has been applied to investigate the pion electroproduction reactions on the nucleon. It is found that the model can describe to a very large extent the recent data of p(e,e'…

The decays of psi(2S) into gamma p bar{p}, pi^0 p bar{p} and eta p bar{p} have been studied with the CLEO-c detector using a sample of 24.5 million psi(2S) events obtained from e^+e^- annihilations at sqrt{s} = 3686 MeV. The data show…