Author:
Wang 王 Ai-Chao 爱超,Wei 韦 Neng-Chang 能昌,Huang 黄 Fei 飞
Abstract
Abstract
The photoproduction of the
meson off the proton target is investigated within an effective Lagrangian approach. The t-channel ρ- and ω-exchange diagrams, u-channel nucleon-exchange diagram, generalized contact term, and s-channel pole diagrams of the nucleon and a minimal number of nucleon resonances are taken into account in constructing the reaction amplitudes to describe the experimental data. Three different models, that is, the Feynman, Regge, and interpolated Regge models, are employed, where the t-channel reaction amplitudes are constructed in Feynman, Regge, and interpolated Regge types, respectively. The results show that neither the Feynman model with two nucleon resonances nor the interpolated Regge model with one nucleon resonance can satisfactorily reproduce the available data for
. Nevertheless, in the Regge model, when any one of the
,
,
,
,
,
,
,
, and
resonances is considered, the data can be well described. The resulting resonance parameters are consistent with those advocated in the Particle Data Group (PDG) review. Further analysis shows that, in the high-energy region, the peaks of
differential cross sections at forward angles are dominated by the contributions from t-channel ρ- and ω-exchange diagrams, while in low-energy region, the s-channel pole diagrams of resonances also provide significant contributions to the
cross sections.
Funder
National Natural Science Foundation of China
China Postdoctoral Science Foundation
Fundamental Research Funds for the Central Universities
Subject
Astronomy and Astrophysics,Instrumentation,Nuclear and High Energy Physics