The collective flow of positive charged kaons in heavy ion reactions at SIS energy is investigated within the frame of covariant kann dynamics. The theoretical results calculated by using quantum molecular dynamics sh...The collective flow of positive charged kaons in heavy ion reactions at SIS energy is investigated within the frame of covariant kann dynamics. The theoretical results calculated by using quantum molecular dynamics show that the rapidity distribution of K^＋ mesons is more sensitive to the nuclear equation of state than the differential directed flow. The contribution of various K^＋ production reaction channels to the rapidity distribution of the K^＋ is also analysed in detail. The results indicate that the rapidity distribution of K^＋ mesons is mainly from the contribution of the N-△ and N-N channel. This means that the delta resonance state plays a predominantly important role for the K^＋ subthreshold production.展开更多
The transverse momentum distributions of Λ's and proton's directed flows are investigated by using Quantum Molecular Dynamics model (QMD) within the framework of covariant kaon dynamics. The calculated result...The transverse momentum distributions of Λ's and proton's directed flows are investigated by using Quantum Molecular Dynamics model (QMD) within the framework of covariant kaon dynamics. The calculated results show that the transverse momentum distribution of differential directed flow of Lambda hyperons is dependent appreciably on the nuclear matter equation of states (EOS). The differential directed flow of Lambda hyperons calculated with soft EOS is consistent with the experimental data,whereas the discrepancy between the results obtained with hard EOS and experimental data increases with increasing the transverse momentum. Although the interaction acting on Λ's by nucleons in the dense medium is attractive,the analysis indicates,that the transverse momentum distribution of proton's directed flow is insensitive to the EOS. The results obtained with both hard and soft EOS are all roughly in agreement with the corresponding data.展开更多
基金Supported by the National Nature Science Foundation of China under Grant Nos 10575075, 10447006 and 10435080, and the Commission on Higher Education of Thailand （CHE-RES-RG Theoretical Physics）.
文摘The collective flow of positive charged kaons in heavy ion reactions at SIS energy is investigated within the frame of covariant kann dynamics. The theoretical results calculated by using quantum molecular dynamics show that the rapidity distribution of K^＋ mesons is more sensitive to the nuclear equation of state than the differential directed flow. The contribution of various K^＋ production reaction channels to the rapidity distribution of the K^＋ is also analysed in detail. The results indicate that the rapidity distribution of K^＋ mesons is mainly from the contribution of the N-△ and N-N channel. This means that the delta resonance state plays a predominantly important role for the K^＋ subthreshold production.
基金supported in part by the National Natural Science Foundation of China (Grant Nos. 10575075, 10447006, 10435080, 10611140542and 10811240295)the Commission on Higher Education of Thailand(CHE-RES-RG Theoretical Physics)
文摘The transverse momentum distributions of Λ's and proton's directed flows are investigated by using Quantum Molecular Dynamics model (QMD) within the framework of covariant kaon dynamics. The calculated results show that the transverse momentum distribution of differential directed flow of Lambda hyperons is dependent appreciably on the nuclear matter equation of states (EOS). The differential directed flow of Lambda hyperons calculated with soft EOS is consistent with the experimental data,whereas the discrepancy between the results obtained with hard EOS and experimental data increases with increasing the transverse momentum. Although the interaction acting on Λ's by nucleons in the dense medium is attractive,the analysis indicates,that the transverse momentum distribution of proton's directed flow is insensitive to the EOS. The results obtained with both hard and soft EOS are all roughly in agreement with the corresponding data.
