Investigation of the anomaly in η-photoproduction off the neutron

作     者：D. Werthmüller 

作者机构：Department of Physics University of Basel Klingelbergstrasse 82 CH-4056 Basel Switzerland 

出 版 物：《Chinese Physics C》 (中国物理C（英文版）)

年 卷 期：2009年第33卷第12期

页      面：1345-1348页

核心收录：

学科分类：07[理学] 08[工学] 0827[工学-核科学与技术] 082701[工学-核能科学与工程] 070202[理学-粒子物理与原子核物理] 0702[理学-物理学] 

基　　金：Supported by Schweizerischer Nationalfonds  DFG  and EU/FP6 

主　　题：photoproduction eta-meson narrow nucleon resonance 

摘      要：Quasi-free photoproduction of wmesons off the neutron and off the proton has been studied using a deuterium target and bremsstrahlung photons produced by MAMI-C with incident energies up to 1.5 GeV. The wmesons were detected in coincidence with the recoil nucleons thus a fully exclusive measurement was performed. Preliminary results show a bump-like structure in the excitation function for the neutron close to W ≈ 1675 MeV which is not seen for the proton. Considering the experimental resolution and using a Breit-Wigner fit the width of this structure was approximated below 50 MeV.