Nuclear matter at a HIRFL-CSR energy regime
Nuclear matter at a HIRFL-CSR energy regime
复制标题
DOI：
10.1088/0954-3899/36/6/064040
复制
发表时间：
2009-06
期刊：
影响因子：
--
通讯作者：
Z. Xiao;Lie-Wen Chen;F. Fu;Bao-An Li;G. Jin;Hushan Xu;G. Yong;Ming Zhang
中科院分区：
文献类型：
--
作者：
Z. Xiao;Lie-Wen Chen;F. Fu;Bao-An Li;G. Jin;Hushan Xu;G. Yong;Ming Zhang
我们报道了利用高能重离子碰撞在高密度下约束对称能Esym(ρ)的一些最新进展。通过比较最近测量的介子比ρ+与π−/π的FOPI以及IBUU04模型的计算，得到了软Esym(GSIM)在超饱和密度下存在的间接证据。详细的研究表明，随着束流能量的降低，从ρ+获得Esym(π−/π)的能力随着束流能量的降低而增强，这与核停止的增加有关。在世界上几个重离子反应装置中，兰州新近投入使用的重离子储存环(HIRFL-CSR)将提供高达1A GeV的重离子束，并与先进的探测器相耦合，将为进一步研究不对称核物质的状态方程做出重要贡献。
We report some recent progress in constraining the symmetry energy Esym(ρ) at high densities using high-energy heavy-ion collisions. Circumstantial evidence of a soft Esym(ρ) at supra-saturation density is obtained by comparing the pion ratio π−/π+ measured recently with FOPI at GSI and the IBUU04 model calculations. Detailed studies indicate that the power of determining the Esym(ρ) from π−/π+ is enhanced with decreasing the beam energy to near the pion production threshold, showing a correlation to the increasing nuclear stopping. Among several heavy-ion reaction facilities in the world, the cooling storage ring (HIRFL-CSR), newly commissioned at Lanzhou, delivering heavy-ion beams up to 1 A GeV, to be coupled with advanced detectors will contribute significantly to further studies of the equation of state of asymmetric nuclear matter.