30MeV/u 40Ar+112,124Sn反应中的同位素产额比与核温度

系统研究了30MeV/u^40Ar ^112,124Sn反应中的轻粒子同位素产额比随角度和初始激发能的变化关系，对于两个反应体系，均观察到3He/^4He和^6Ni/^7Li的产额比随角度的增加而增加，^6He/^4He和^8Li/^7Li随角度的增加而减少，统计发射的运动学效应不能完全符合实验结果，各种单同位素产额比与靶核的N／Z比有关，表现出同位旋效应，而由双同位素比提取的核温度几乎没有靶核相关性。

Isotope Ratios of Light Charged Particles and Temperature in the Reactions 30MeV/u 40Ar+112,124Sn

Coincidence measurements between residues and light charged particles (LCPs) have been made for the reactions 30MeV/u 40Ar+ 112,124Sn. The LCPs were measured by 11 semi conduct telescopes from very forward angle to backward angle. The times of flight of the residues were measured by PPACs installed concentrically around the beam at forward angle. The excitation energy of the primary hot nuclei was obtained from the velocity of residues in the frame of incomplete fusion model. The single isotope ratios, as function of observing angle and excitation energy have been studied. The ratio of 3He/ 4He and 6Li/ 7Li increases with angle while that of 6He/ 4He and 8Li/ 7Li decreases. The calculation of statistical theory can not reproduce the curve quantitatively, implying the existence of dynamic effect. Isospin effect of the primary hot nuclei on the single isotopic ratios is demonstrated. However, the temperature extracted from double isotope ratios is target independent.