Measurements of keV-Neutron Capture Cross Sections and Capture Gamma-Ray Spectra of^117,119Sn

Abstract

The neutron capture cross sections and the capture -ray spectra of 117;119 Sn were measured in an energy region from 15 to 100 keV and around 550 keV. A neutron time-of-flight method was adopted with a ns-pulsed neutron source based on the 7 Li(p,n) 7 Be reaction and with a large anti-Compton NaI(Tl) spectrometer. A pulse-height weighting technique was applied to the observed capture -ray pulse-height spectra to obtain the capture yields. Using the standard capture cross sections of 197 Au, the capture cross sections of 117;119 Sn were derived with the errors less than 5%. The capture -ray spectra were obtained by unfolding the observed capture -ray pulse-height spectra. The present results for the capture cross sections are compared with the previous experimental values and the evaluated values of JENDL-3.3, and ENDF/B-VI.8 and VII.0.