原子核物理评论
原子覈物理評論
원자핵물리평론
Nuclear Physics Review
2014年
3期
326-332
,共7页
兰州量子分子动力学模型%K-核子相互作用势%对称能%K0/K+
蘭州量子分子動力學模型%K-覈子相互作用勢%對稱能%K0/K+
란주양자분자동역학모형%K-핵자상호작용세%대칭능%K0/K+
LQMD model%kaon-nucleon potential%symmetry energy%K0/K+ ratio
基于兰州量子分子动力学(LQMD)模型研究了阈能附近K介子(K0和K+)产生动力学机制。LQMD模型能够较好地描述中能重离子碰撞中K介子产额分布。通过拟合K介子动能谱分布，计算中采用了排斥的K-核子相互作用势。该光学势增强了高动量K介子产生，而降低了K介子总产额。结合实验数据比较，在高密区域给出了较软的对称核物质状态方程。对称能的软硬对K0/K+比值起着重要作用，特别是在阈下区域。而K介子光学势对K0/K+比值激发函数影响不明显。
基于蘭州量子分子動力學(LQMD)模型研究瞭閾能附近K介子(K0和K+)產生動力學機製。LQMD模型能夠較好地描述中能重離子踫撞中K介子產額分佈。通過擬閤K介子動能譜分佈，計算中採用瞭排斥的K-覈子相互作用勢。該光學勢增彊瞭高動量K介子產生，而降低瞭K介子總產額。結閤實驗數據比較，在高密區域給齣瞭較軟的對稱覈物質狀態方程。對稱能的軟硬對K0/K+比值起著重要作用，特彆是在閾下區域。而K介子光學勢對K0/K+比值激髮函數影響不明顯。
기우란주양자분자동역학(LQMD)모형연구료역능부근K개자(K0화K+)산생동역학궤제。LQMD모형능구교호지묘술중능중리자팽당중K개자산액분포。통과의합K개자동능보분포，계산중채용료배척적K-핵자상호작용세。해광학세증강료고동량K개자산생，이강저료K개자총산액。결합실험수거비교，재고밀구역급출료교연적대칭핵물질상태방정。대칭능적연경대K0/K+비치기착중요작용，특별시재역하구역。이K개자광학세대K0/K+비치격발함수영향불명현。
Dynamics of kaons (K0 and K+) produced in nuclear reactions near threshold energies has been investigated within the Lanzhou quantum molecular dynamics (LQMD) transport model. The production yields are consistent with the available experimental data. A repulsive kaon-nucleon potential is implemented in the model through fitting the kinetic energy spectra of inclusive cross sections in heavy-ion collisions, which enhances the energetic kaon emission squeezed out in the reaction zone and reduces the total kaon yields. The comparison to the available data supports a soft equation of state in the density region of 2～3ρ0 for isospin symmetric nuclear matter. It is found that the stiffness of nuclear symmetry energy plays a significant role on the isospin ratio with decreasing the incident energy, in particularly in the domain of subthreshold energies.
