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

Abstract

The neutron capture cross sections and the capture γ-ray spectra of ^117,119Sn 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 ⁷Li(p,n)⁷Be reaction and with a large anti-Compton NaI(Tl) spectrometer. A pulse-height weighting technique was applied to the observed capture γ-ray pulse-height spectra to obtain the capture yields. Using the standard capture cross sections of ¹⁹⁷Au, the capture cross sections of ^117,119Sn were derived with the errors less than 5%. The capture γ-ray spectra were obtained by unfolding the observed capture γ-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.

KEYWORDS:

• neutron capture
• cross sections
• gamma spectra
• keV range
• tin 117
• tin 119
• gold 197
• anti-Compton NaI(Tl) spectrometer
• time-of-flight method
• pulse-height weighting technique
• experimental data