Data on the production of vector mesons ρ and ω in the backward direction via nucleon exchange areinvestigated. A better understanding of these data is achieved than hitherto, albeit at a semi-quantitative level. Th...Data on the production of vector mesons ρ and ω in the backward direction via nucleon exchange areinvestigated. A better understanding of these data is achieved than hitherto, albeit at a semi-quantitative level. Thisis achieved partly by using more up-to-date values for the vector couplings and partly by using more precise theoreticalformalism. In view of this we conclude that the data do provide a useful constraint on the couplings.展开更多
Some analyses of the electromagnetic form factors of the nucleon and some analyses of the nucleon-nucleon potential favor a large coupling of the φ meson to nucleons. This is frequently quoted by advocates of a large...Some analyses of the electromagnetic form factors of the nucleon and some analyses of the nucleon-nucleon potential favor a large coupling of the φ meson to nucleons. This is frequently quoted by advocates of a large ss component of the nucleon. It is shown that such large OZI-violating couplings are incompatible with data on φproduction in backward direction via nucleon exchange.展开更多
The N/Z ratio of free nucleons from collisions of neutron-rich nuclei as a function of their momentum is studied by means of isospin-dependent Quantum Molecular Dynamics. We find that this ratio is not only sensitive ...The N/Z ratio of free nucleons from collisions of neutron-rich nuclei as a function of their momentum is studied by means of isospin-dependent Quantum Molecular Dynamics. We find that this ratio is not only sensitive to the form of the density dependence of the symmetry potential energy but also its strength determined by the symmetry energy coefficient. The uncertainties about the symmetry energy coefficient influence the accuracy of probing the density dependence of the symmetry energy by means of the N/Z ratio of free nucleons of neutron-rich nuclei.展开更多
文摘Data on the production of vector mesons ρ and ω in the backward direction via nucleon exchange areinvestigated. A better understanding of these data is achieved than hitherto, albeit at a semi-quantitative level. Thisis achieved partly by using more up-to-date values for the vector couplings and partly by using more precise theoreticalformalism. In view of this we conclude that the data do provide a useful constraint on the couplings.
文摘Some analyses of the electromagnetic form factors of the nucleon and some analyses of the nucleon-nucleon potential favor a large coupling of the φ meson to nucleons. This is frequently quoted by advocates of a large ss component of the nucleon. It is shown that such large OZI-violating couplings are incompatible with data on φproduction in backward direction via nucleon exchange.
基金The project supported by National Natural Science Foundation of China under Grant Nos.10175093 and 10235030+4 种基金the Science Foundation of Chinese Nuclear Industry and the State Key Basic Research Development Program under Contract No.G20000774the Knowledge Innovation Project of the Chinese Academy of Sciences under Grant No.KJCX2-SW-N02the CASK.C.Wong Post-doctors Research Award Fund
文摘The N/Z ratio of free nucleons from collisions of neutron-rich nuclei as a function of their momentum is studied by means of isospin-dependent Quantum Molecular Dynamics. We find that this ratio is not only sensitive to the form of the density dependence of the symmetry potential energy but also its strength determined by the symmetry energy coefficient. The uncertainties about the symmetry energy coefficient influence the accuracy of probing the density dependence of the symmetry energy by means of the N/Z ratio of free nucleons of neutron-rich nuclei.