Article,
Measurement of cross sections for $\alpha$-induced reactions on Au197 and thick-target yields for the ($\alpha$,$\gamma$) process on Zn64 and Cu63
Phys. Rev. C, 75 (1): 015802 (January 2007)
DOI: 10.1103/PhysRevC.75.015802
Abstract
We have measured the cross sections for the $^197$Au($\alpha$,$\gamma$)201Tl and $^197$Au($\alpha$,2n)199Tl reactions in the 17.9- to 23.9-MeV energy range, and $^197$Au($\alpha$,n)200Tl reaction in the 13.4- to 23.9-MeV energy range using an activation technique. Thick-target yields for the 64Zn($\alpha$,$\gamma$)68Ge (7- to 14-MeV) and 63Cu($\alpha$,$\gamma$)67Ga (7-MeV) reactions were measured. For all measurements, natural elements were bombarded with He+ beams from the 88 In. Cyclotron at the Lawrence Berkeley National Laboratory (LBNL). Irradiated samples were counted using a $\gamma$-spectrometry system at LBNL's Low Background Facility. Measured $^197$Au($\alpha$,$\gamma$)201Tl cross sections were compared with the NON-SMOKER theoretical values. The thick-target yields for the 64Zn($\alpha$,$\gamma$)68Ge and 63Cu($\alpha$,$\gamma$)67Ga reactions are also compared with the theoretical yield, calculated numerically using the energy dependent NON-SMOKER cross section data. In both cases, measured values are found to follow a trend of overlapping the predicted value near the alpha nucleus barrier height and fall below with a slowly widening difference between them in the sub-barrier energy points.
