Feng, ZQ (reprint author), Chinese Acad Sci, Inst Modern Phys, Lanzhou 730000, Peoples R China.
[Feng, Zhao-Qing] Chinese Acad Sci, Inst Modern Phys, Lanzhou 730000, Peoples R China
The quantum molecular dynamics model has been improved to investigate the reaction dynamics induced by antiprotons. The reaction channels of elastic scattering, annihilation, charge exchange, and inelastic collisions have been included in the model. Dynamics on particle production, in particular pions, kaons, antikaons, and hyperons, is investigated in collisions of (p) over bar on C-12, Ne-20, Ca-40, Sn-112, Ta-181, Au-197, and U-238 from a low to high incident momentum. The rapidity and momentum distributions of pi(+) and protons from the LEAR measurements can be well reproduced. The impacts of system size and incident momentum on particle emissions are investigated from the inclusive spectra, transverse momentum, and rapidity distributions. It is found that the annihilations of (p) over bar on nucleons are of importance on the particle production. Hyperons are mainly produced via meson induced reactions on nucleons and strangeness exchange collisions when the incident momentum is below the threshold value of annihilation reaction. A higher nuclear temperature is obtained from the kaon emission, but it has a lower value for hyperon production.