Total Cross Sections for Kilovolt Neutrons of Even-Odd Nuclei in the Region of the 3s Strength-Function Resonances

Neutron total cross sections of seperated isotopes were measured with the time-of-flight spectrometer at the 3 MeV Karlsruhe Van do Graaff Accelerator. The neutron energy ranged from 10 to 250 keV. The energy resolution was between 0.2 and 0.5 nsce/m. The measured cross sections were-shape-analyzed in terms of an R-matrix multilevel formula. Thus neutron widths and spins for up to 50 resonances per isotope could be determined. Average neutron widths, level densities and strength functions were derived. The spin dependence of strength functions and the distribution of widths and spacings were investigated.

Karlsruhe 3 MeV pulsed Van do Graaff 사용 중성자비행시간법으로 농축된 동위원소 들의 중성자 전단면적을 측정하였다. 중성자 에너지 영역은 10kev로부터 250keV이며 에너지 분해능은 0.2와 0.5 nsec/m 사이이다. 측정된 전단면적은 R-matrix. multi-level formula로 shape-analysis를 했다. 각 원소당 50주 가까운 공조에 대하여 중성자폭과 Spin을 결정할 수 있었다. 평균중성자폭, 준위밀도, Strength function도 결정하였다. Strength function의 Spin의존성, 중성자폭분포 및 준위간 간격도 함께 규명하였다.