摘要
通过对 ２５ＭｅＶ／ｕ４０Ａｒ＋１１５ Ｉｎ反应 θｌａｂ＝ １５°的邻近几何条件下的轻带电粒子和出射碎片之间的关联测量，观察到了两体相继衰变机制的存在．其中，轻带电粒子和碎片的关联角度谱在小角度成峰，最可几角度约２°左右；轻带电粒子能谱峰位，随关联对的质量增加而逐渐增高；质量较轻的原始产物容易受到激发，通过发射轻带电粒子而衰变成轻中等质量碎片．在两体相继衰变中，原始激发产物发射重质量的轻带电粒子的产额或几率要大于质量轻的轻带电粒子，具体测量发现，与轻带电粒子１１，２１Ｈ，３１Ｈ和ａ粒子关联的碎片（Ｚｆ＝４—１４）总的产额比为１：１．３：１．７８：７．５７．
The correlations between the emitted fragments at θlab = 15° and the light charged particles(LCPs) at the close geometry configuration in the reaction of 25MeV/u 40Ar + 115 In were measured. The energy correlations between fragments (4≤Zf≤14) and the LCPs including proton, deuterium, tritium and a particle as well as the energy spectra of the LCPs were obtained. The result shows the existence of sequential decay mechanism. It is found that the peak position of angular correlation is at the small angles and the most probable correlation angle is at 2° or so; The peak positions of the two components in the energy spectra of LCPs increase gradually with the mass of correlated partner; The lighter primaly products are more easier to be excited and decay to IMFs and the LCPs. In the Sequential decay, the yield of the LCPs with more heavier mass is higher than that of the lighter LCPs. The result reveals that the total correlation yield ratios summed over the fragments of Zf = 4-14 are 1: 1. 3: 1. 78: 7. 57 for proton, deuterium, tritium and a particles, respectively.
出处
《高能物理与核物理》
EI
CSCD
北大核心
2001年第2期115-120,共6页
High Energy Physics and Nuclear Physics
基金
国家自然科学基金!(19475054)资助
