25 MeV/u^(40)Ar+^(197)Au反应中高激发热核的时空演化  

SPACE TIME EVOLUTION OF HIGHLY EXCITED NUCLEUS FROM 40 Ar+ 197 Au REACTIONS AT 25MeV/NUCLEON *

作　　者：贺智勇[1] 靳根明[1] 李祖玉[1] 段利敏[1] 戴光曦[1] 吴和宇[1] 张保国[1] 文万信[1] 漆玉金 罗清政 王宏伟[1] 王素芳[1] 

机构地区：[1]中国科学院近代物理研究所

出　　处：《物理学报》1998年第6期916-921,共6页Acta Physica Sinica

基　　金：国家自然科学基金;中国科学院重点项目

摘　　要：报道了２５ＭｅＶ／ｕ４０Ａｒ＋１９７Ａｕ反应中从两粒子相对动量关联函数提取的发射时间随空间大小演化的规律．结果表明，即使发射源质量数减小５０％，对计算的关联函数及提取的发射时间影响仍然很小．在短发射时间（τ≤１００ｆｍ／ｃ）情况下，较小的核物质密度，导致提取的发射时间变小．因此，在正常核物质密度参数下提取的τ值可作为发射时间的上限值．在长发射时间（τ≥３００ｆｍ／ｃ）情况下发射时间不随空间大小变化，提取的τ即为实际的发射时间．Abstract The emission time extracted from two particle relative momentum correlation functions has been studied as a function of the spatial extent of the source for 40 Ar+ 197 Au reaction at 25MeV/u.Reduction of ～50% in the mass number of the source has a very small effect on the calculated correlation functions and the extracted emission time.For the cases of short emission time τ(τ ≤100fm/ c ), use of a smaller nuclear density would lead to somewhat smaller assignment for τ ;therefore,these τ values extracted in the normal nuclear density can be taken as upper limits of τ values.For the cases of long emission time ( τ ≥300fm/ c ),the emission times do not vary with the size of the source and these τ values can be taken as the real values.

关 键 词：氩40 金197 重离子 高激发 热核反应 时空演化 

分 类 号：O571.426[理学—粒子物理与原子核物理]