Status of JENDL

Abstract

Recent progress and future plan of the JENDL project are summarized. Two special purpose files were released recently. One is Photo-nuclear Data File 2016 (JENDL/PD-2016) which contains the data of photo-nuclear reaction cross sections covering a wide area of the nuclear chart. The other one is the JENDL Activation Cross Section File for Nuclear Decommissioning 2017 (JENDL/AD-2017) which provides production cross sections of radioactive nuclei by neutrons. A special purpose file JENDL/ImPACT-2018 dedicated to transmutation of long-lived fission products will be released in 2019. Regarding the general-purpose file, we are preparing to release the next version, which would be made available by 2022 as JENDL-5. Evaluation efforts on nuclides across wide range of nuclei form light to heavy have being made. The first test version JENDL-5α1 was created in 2018. The evaluated data will be updated on the basis of benchmark tests on reactor criticalities and neutron shieldings.

99Tc in stars, reactors, and nuclear medicine

“…The present results are shown in Fig. 7, and compared with other measurements [31-33, 38, 39] and the evaluated values in JENDL-5 [40], ENDF/B-VIII.0 [41], and JEFF-3.3 [42].…”

Measurement of the $^{236}$U fission cross section and angular distributions of fragments from fission of $^{235}$U and $^{236}$U in neutron energy range of 0.3-500 MeV

“…In this case, the data on the isotopic composition of the targets and the half-lives of the corresponding isotopes presented in the Table II were used. The masses were found to be 3.480(48) mg and 5.796 (44) mg with relative statistical uncertainty 0.9% and 0.2% for the 235 U and 236 U nuclei, respectively. The average substance thicknesses in the selected circles found from these masses are 192(3) µg/cm 2 and 320(2) µg/cm 2 for the targets of 235 U and 236 U, respectively.…”

“…Fig. 20 shows the variation that exists between different national libraries of evaluated data: JEFF-3.3 [43], JENDL-5 [44], CENDL-3.2 [45], and ENDF/B-VIII.0 (note that the ENDF/B-VIII.0 evaluation in the neutron energy range below 20 MeV coincides with the ROSFOND-2010 evaluation [46]). In the energy range of 1-20 MeV, all evaluations agree with each other within ∼ 3%, with the exception of the European evaluation JEFF-3.3, according to which the fission cross section of 236 U in the neutron energy range from 1.5 MeV to 3 MeV is underestimated by 5-8% relative to other estimates.…”

The impact of n_TOF data on s-process modelling

“…Results have been reported for stable and radioactive samples, i.e., 24,25,26 Mg, 54,57 Fe, 58,59,62,63 Ni, 70,72,73 Ge, 90,91,92,93,94,96 Zr, 139 La, 140 Ce, 147 Pm, 151 Sm, 154,155,157 Gd, 171 Tm, 186,187,188 Os, 197 Au, 203,204 Tl, 204,206,207 Pb and 209 Bi isotopes (see [8] for more details), and others are being studied or planned to be studied in the near future. In some cases, these results were then used to improve Evaluated Nuclear Data File such as ENDF/B-VIII.0 [9], JENDL-5.0 [10] and JEFF-3.3 [11] or TENDL-2021 [12] and other international projects. The same data were used to derive the neutron-induced cross section averaged over the stellar neutron-energy distribution, typically referred to as Maxwellian averaged cross section (MACS) -more details in Sec.…”