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本实验测量了C12(d,p)C13及Ca40(d,p)Ca41基态反应质子群的角分布和微分截面。氘核能量为13.3MeV,对C12和Ca40的反应,其测量角度范围分别为3°—167°和10°—164°,每隔2.5°或5°测量一点,其主要结果如下:(1)对于这两群质子,在主削裂峯附近的实验点和用简单Butler理论算得的理论角分布曲线都符合得相当好;理论计算数据对实验数据在主峯处归一;由此而定得的核能级参数与前人所得到的是一致的。(2)大角度区的实验截面数值没有减小到象Butler理论所要求的那样小,并有非常明显的次极大出现,其位置与Butler理论所预言的不一致;这些特点可以用扭曲波理论来解释,非氘核削裂机制也可能有部分贡献。(3)在C12(d,p)C13反应中,前角度区的截面有很大下降,而后角区则有明显的增加,这些现象都和Butler理论不一致;然而,这也可以用扭曲波来解释。(4)用主峯处的截面和Butler理论算得的基态的约化宽度,对C12(d,p)C13和Ca40(d,p)Ca41反应分别为r2=0.17和0.041;用扭曲波理论计算时,则得到较大的r2值,后者更接近于单粒子模型所预言的数值,基于上面这些事实,对本实验的数据使用扭曲波理论来进行分析似乎是值得的。The angular distribution and differential cross-section of the proton groups from the C12(d,p)C13 and Ca40(d,p)Ca41 ground state reactions have been measured at the deu-teron energy of 13.3 MeV. Measurements were made at 2.5° or 5° intervals and covered the angular range from 3° to 167° and from 10° to 164° for the C12 and Ca40 reactions respectively. It is found that: (1) The experimental points near the main stripping peak agree fairly well with the theoretical angular distribution curve calculated by using the simple Butler theory and normalized at the stripping peak, for both proton groups. The parameters of the nuclear levels thus determined are in good accord with the results previously obtained. (2) For large angles, the experimental cross-sections do not decrease to such small values as required by the Butler theory. They also show very prominent subsidiary maxima at the positions not in accord with the prediction of the Butler theory. These features can be interpreted by the distorted wave theory, but may also be partly due to contributions of reaction mechanisms other than the deuteron stripping. (3) In the C12(d, p)C13 reaction, the cross-section decreases strongly at the forward angle and shows an uprising at the backward angle. Neither of these features is in accord with the Butler theory, but they can also be explained by the distorted wave theory. The uprising at the backward angle may also be due to contributions of other reaction mechanisms. (4) The reduced widths of the ground levels for the C12(d, p)C13 and Ca40(d, p)Ca41 reactions, obtained from the peak cross-sections by using the Butler theory are γ2 = 0-17 and 0.041 respectively. The distorted wave theory gives larger values which will be closer to the values expected from the single particle model. Owing to these facts, it seems worthwhile to analyze the data of the present experiment with the detailed distorted wave theory.
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