Measurement of keV-Neutron Capture Cross Sections and Capture Gamma-Ray Spectra of ^<140>Ce and ^<141>Pr

概要

論文の詳細を見る
The neutron capture cross sections and capture γ-ray spectra of 140Ce and 141Pr were measured in the neutron energy region of 10 to 100 keV and at 550 keV. Prompt γ rays from a capture sample were detected with a large anti-Compton NaI(Tl) spectrometer, employing a neutron time-of-flight method with a 1.5-ns pulsed neutron source by the 7Li(p, n)7Be reaction. A pulse-height weighting technique was applied to observed capture γ-ray pulse-height spectra to extract capture yields. The capture cross sections were derived with the error of about 5% by using the standard capture cross sections of 197Au. The present results were compared with evaluated values in JENDL-3.2 and previous measurements. The capture γ-ray spectra were obtained by unfolding the observed capture γ-ray pulse-height spectra. An anomalous bump was observed around 1.5 MeV in each γ-ray spectrum of 140Ce and 141Pr, and its energy position was consistent with the systematics obtained in our previous work. The multiplicities of the observed capture γ rays were derived from the γ-ray spectra.
社団法人日本原子力学会の論文
2000-09-25