摘要: 深垒下能区的¹²C+¹³C熔合截面测量对检验天体中熔合反应外推模型具有很重要的意义。目前在库仑位垒以下能区存在的各种测量结果，都利用了统计模型来修正得到熔合截面，但对于这些方法间的系统误差仍没有很好地研究。实验采用离线活度测量的方法，在E_c.m.=4.4～5.8 MeV能区内对¹²C+¹³C熔合截面进行测量。经Hauser-Feshbach统计模型对分支比的修正后，熔合总截面由²⁴Na活度推导出。通过本实验数据与其它实验方法获得的数据进行比较，确定了统计模型的系统误差为14%。


The study of fusion reactions of ¹²C+¹³C at the deep sub-barrier energies is very important for the test of predictive power of the extrapolation models for nuclear reactions for astrophysics. Until now, all the measurements below Coulomb barrier energies have to use the statistical model calculations to estimate the branching ratios to deduce the total fusion cross sections. However, the systematic uncertainty induced by the calculated corrections has not been studied well. In this experiment, the fusion cross sections of ¹²C+¹³C have been measured using an offline activity measurement in the range of E_c.m.=4.4 to 5.8 MeV. The total fusion cross sections have been deduced from the ²⁴Na activities after correcting the branching ratios estimated with the Hauser-Feshbach statistical model. Through the comparison between our result and other data obtained with other methods, the systematic uncertainty of statistical model has been determined to be 14%.