论文信息 - Absolute Cross Sections of the (γ, n) Reaction for Cu 63 , Zn 64 and Ag 109

Absolute Cross Sections of the (γ, n) Reaction for Cu 63 , Zn 64 and Ag 109

The photonuclear reaction cross section of Cu/sup 63/ ( gamma , n)Cu/sup 62/ has been frequently used as the standard for the ( gamma , n) reactions, but measured values by many workers do not agree with one another and can be roughly divided into two groups, namely, about l00 mb group and about 50 mb group. It appears that the former group contains the values obtained mainly from measurements through use of bremsstrahlung, while the latter were obtained mainly with Li(p, gamma ) gamma rays. Attempts were made to re-determine the ( gamma , n) cross section for copper, zinc, and silver by Li(p, gamma ) gamma rays. Absolute measurement or gamma quanta was performed by Hough's method, and reaction yields were determined by the activation method in which the absolute numbers of activated nuclei in samples were determined by measuring the BETA ray with a 4 pi proportional counter and applying the method of extrapolation.'' The cross sections of Cu/sup 63/, Zn/sup 64/, and Ag/sup 109/ for l7.6-Mev gamma rays were foundto be 42.5 mb plus or minus 15%, 23.3 mb plus or minus 18%, and 61.5 mb plus or minus 16%, respectively. Experimental cross sections so farmore » obtained by many workers are compiled, and discussions are given. (auth)« less

K. Takamatsu | K. Fukunaga | Teruo Nakamura | S. Yasumi | M. Yata

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