【摘要】 本工作采用固体径迹探测器（天然白云母）测量了72.7,69.6,67.4,65.4,63.4和61.4MeV¹²C离子轰击¹⁸¹Ta,W,Re,Pt,¹⁹⁷Au,Pb和²⁰⁹Bi等裂变反应碎片角分布。由相当于全部动量转移的裂变事件的碎片角分布统计理论分析直接确定了形成全熔合的临界角动量l_cr,根据锐截止模型计算了全熔合截面σ_fu。结果和按照R.Bass模型计算的全熔合激发函数做了比较。我们还分析了已经发表过的¹⁴N+Pb和¹²C+²³⁸U碎片角分布数据,由对碎片角分布数据理论分析得到的全熔合截面σ_fu和直接测量的结果很好的符合。更多还原

【Abstract】 We have measured the angular distributions of fission fragnents for a series ofcompound nuclei formed in the bombardment of ¹⁸¹Ta, W, Re, Pt, ¹⁹⁷Au, Pb and ²⁰⁹Biby 72.7, 69.6, 67.4, 65.4, 63.4 and 61.4 MeV ¹²C ions with mica track detectors. Thecritical angular momentum l_cr. can be determined directly from the statistical analysisof the fission fragment angular distribution corresponding to the fission events withfull momentum transfer. The complete fusion cross section σ_fu were calculated on thebasis of the sharp cut-off model. The results for l_cr obtained by this method were com-pared with those predicted by R. Bass model. The published data on fission fragmentangular distributions of ¹⁴N+Pb and ¹²C+²³⁸U reactions were also analyzed by thismethod. The values of σ_fu are found to be in good agreement with the direct comple-te fusion cross section measurements.更多还原