Activation cross-sections for some 14·8 MeV neutron-induced nuclear reactions on caesium: Isomer ratios of 134Cs, 133Xe and 130I

Neutron Nuclear Data Evaluation of Cesium Isotopes for JENDL-4.0

“…Hence, the data of Bormann and his group were excluded from this evaluation. Qaim 28) reported a cross section reasonable with other measurements. The cross sections measured are about 1.6 b around 14.5 MeV.…”

“…5, though larger cross sections of about 7 mb were reported by Qaim 28) and Ma et al 45) For unstable 135 Cs with a half-life of 2:3 Â 10 6 yr, the capture cross section was measured by Patronis et al 7) by the activation technique. The JENDL-4.0 evaluation was carried out to reproduce the experimental data at 30 and 500 keV.…”

“…Capture Cross Section Figure 5 illustrates capture cross sections for 133{137 Cs in JENDL-4.0, which are compared with those of the measurements 7,28,32,33,41,[44][45][46][47][48][49][50][51] and of JENDL-3.3, ENDF/B-VII.0 and JEFF-3.1.1. Figure 6 focuses on the present result for 133 Cs in the keV region, whose evaluation was based on the average cross sections derived by Macklin. 44) The JENDL-4.0 data have slightly large cross sections relative to those of Yamamuro et al 46) and Bokhovko et al 47) in the incident energies below 80 keV, above which the influence of inelastic scattering becomes important.…”

“…7, in which the calculated results are compared with experimental data. 6,28,33,45,[50][51][52][53] In the present evaluation, the 720.4 keV level was assumed as the highest discrete level in 134 Cs (see Table 2). At the thermal energy, experimental data 52,53) show values marginally consistent with the present result (0.064).…”

“…The parameter f was chosen to be 1.1 for 133;134 Cs and 0.85 for 133 Xe in order to fit experimental data 28) for the 133 Cs(n; p) reaction. The values of f ¼ 1:1 and 0.85 were also applied to the other Cs and Xe isotopes, respectively.…”