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The total and double differential scattering cross sections (DDSCS) of isotropic graphite have been measured in the J-PARC Materials and Life Science Experimental Facility using five samples with different porosities and grain sizes. The DDSCS measurements were performed in Beam Line No.14 (AMATERAS) with nine incident neutron energies ranging from 1.2 to 94 meV. In the derived cross sections, there are no clear sample dependence. The neutron total cross sections in the energy region from 1 to 100 meV were measured using Beam Line No. 04 (ANNRI). All samples in the epithermal range (over 40 meV) tended to have values close to the free atom cross-section of graphite. However, at the first Bragg edge, the deduced total cross sections by these measurements started to vary. The difference became more significant with decreasing the neutron energy.

As nuclear facilities are dismantled in decommissioning, various and large amounts of waste are generated. Even more inconveniently, they are radioactive waste due to neutron activation. Thus, the neutron capture cross-sections of nuclides targeted for decommissioning are required to evaluate the radioactivity produced. The present study selected 45Sc, 63Cu, 64Zn, 109Ag and 113In among targeted nuclides, and performed the measurements of thermal-neutron capture cross-sections by an activation method at the Kyoto University Research Reactor. The thermal-neutron capture cross-sections were derived on the basis of Westcott's convention. The present results were obtained as follows: 27.18 ± 0.28 barn for 45Sc(n,γ)46Sc, 4.34 ± 0.06 barn for 63Cu(n,γ)64Cu, 0.719 ± 0.011 barn for 64Zn(n,γ)65Zn, 4.05 ± 0.05 barn for 109Ag(n,γ)110mAg and 8.53 ± 0.27 barn for 113In(n,γ)114Inm1+m2 reactions. The results for 45Sc and 64Zn support evaluated cross-section data within the limits of uncertainties, while those for the other nuclides were slightly different from evaluated ones. The obtained results are useful not only for the evaluation of isotope production, but also for the consideration of those nuclides as flux monitors, as an alternative to Au and Co. [ABSTRACT FROM AUTHOR]

Thermal neutron capture cross-section for191Ir, ${{\rm{\sigma }}_{{\rm{Ir}}}}$ σ Ir (Eth), is a prominent parameter in producing192Ir radionuclide used in high-dose-rate brachytherapy. However, considerable discrepancies exist in past measurements using the activation method and a derived cross-section data calculation from positive resonance parameters of 191Ir, which were measured using the neutron time-of-flight (TOF) method. Therefore, for the first time, we aimed to measure the ${{\rm{\sigma }}_{{\rm{Ir}}}}$ σ Ir (Eth) accurately using the neutron TOF method. Experiments were performed using a pulsed neutron beam and a NaI(Tl) detector at the Accurate Neutron–Nucleus Reaction Measurement Instrument of the Materials and Life Science Experimental Facility in the J-PARC. The ${{\rm{\sigma }}_{{\rm{Ir}}}}$ σ Ir (Eth) was derived from the capture yield using the pulse height weighting technique. As a result, this study obtained the ${{\rm{\sigma }}_{{\rm{Ir}}}}$ σ Ir (Eth) as 949 ± 80 b. The result agrees with some activation data and the evaluated nuclear data libraries, JENDL-5 and ENDF/B-VIII.0, within its uncertainty of 8.4%. This study provides a data reference for the ${{\rm{\sigma }}_{{\rm{Ir}}}}$ σ Ir (Eth) measurement using the neutron TOF method. [ABSTRACT FROM AUTHOR]

Obesity is a major global health concern. Studies suggest that the gut microflora may play a role in protecting against obesity. Probiotics, including lactic acid bacteria and Bifidobacterium, have garnered attention for their potential in obesity prevention. However, the effects of Bifidobacterium-fermented products on obesity have not been thoroughly elucidated. Bifidobacterium, which exists in the gut of animals, is known to enhance lipid metabolism. During fermentation, it produces acetic acid, which has been reported to improve glucose tolerance and insulin resistance, and exhibit anti-obesity and anti-diabetic effects. Functional foods have been very popular around the world, and fermented milk is a good candidate for enrichment with probiotics. In this study, we aim to evaluate the beneficial effects of milks fermented with Bifidobacterium strains on energy metabolism and obesity prevention. Three Bifidobacterium strains (Bif-15, Bif-30, and Bif-39), isolated from newborn human feces, were assessed for their acetic acid production and viability in milk. These strains were used to ferment milk. Otsuka–Long–Evans Tokushima Fatty (OLETF) rats administered Bif-15-fermented milk showed significantly lower weight gain compared to those in the water group. The phosphorylation of AMPK was increased and the expression of lipogenic genes was suppressed in the liver of rats given Bif-15-fermented milk. Additionally, gene expression related to respiratory metabolism was significantly increased in the soleus muscle of rats given Bif-15-fermented milk. These findings suggest that milk fermented with the Bifidobacterium strain Bif-15 can improve lipid metabolism and suppress obesity. [ABSTRACT FROM AUTHOR]

The neutron capture cross section of 243Am from thermal to 100 keV was measured using the Accurate Neutron-Nucleus Reaction Measurement Instrument (ANNRI) at the Japan Proton Accelerator Research Complex (J-PARC). The time-of-flight (TOF) method using a NaI(Tl) detector was employed in these measurements and the pulse-height weighting technique was used to derive the neutron capture yield. The preliminary cross section was determined by normalizing the results to JENDL-4.0 cross section data at the third resonance of 243Am. In the thermal energy, the preliminary result is in good agreement with the two latest experimental data measured by the TOF and the activation methods but higher than the evaluated values in JENDL-5.

The neutron capture cross sections of 107Pd were measured using the Accurate Neutron-Nucleus Reaction Measurement Instrument (ANNRI) at the Japan Proton Accelerator Research Complex (J-PARC). Capture γ-rays were detected with a NaI(Tl) spectrometer. The incident neutron energy was determined by the time-of-flight method. The preliminary cross section was derived from thermal to resonance energy region. In the resonance region, resonance parameters were derived by resonance analysis using REFIT code. The resonance parameter was close to the value of JENDL-4.0.

Japanese Evaluated Nuclear Data Library version 5 (JENDL-5) was released in 2021. JENDL-5 is intended to extend its generality from JENDL-4.0 by covering a wide variety of nuclear data for applications not only to nuclear design and decommissioning, but also to other radiation-related fields. Overview of JENDL-5 and a plan for the next of JENDL-5 are presented.

The neutron capture cross sections of 237Np, 243Am and 241Am in the keV energy region were measured by the time-of-flight method at the Japan Proton Accelerator Research Complex (J-PARC). Characterization of the minor actinide samples were made to reduce the uncertainties of the cross section. A neutron beam filter system was developed and installed in ANNRI to solve the double-bunch mode issue of J-PARC. The pulse-height weighting technique was employed to determine the neutron capture cross sections. The neutron capture cross sections of 237Np, 243Am and 241Am were determined with higher accuracies than the past experiments.

In resonance analyses, experimental uncertainties affect the accuracy of resonance parameters. The resonance analysis code REFIT can consider the statistical uncertainty of the experimental data when evaluating the resonance parameter uncertainty. However, since the systematic uncertainties are not independent at each measured energy, they must be treated differently from the statistical uncertainty. In the present study, we developed a new method to incorporate the systematic uncertainty coming from sample thickness into the uncertainty of resonance parameters. We applied this method to transmission of natural zinc measured at ANNRI of MLF in J-PARC and derived the systematic uncertainty of resonance parameters. We found that some of resonance parameters have larger systematic uncertainties than the statistical ones.

To improve data accuracy of neutron-capture and total cross sections of minor actinides and long-lived fission products, the time-of-flight experimental instrument named ”Accurate Neutron-Nucleus Reaction measurement Instrument” was constructed, and neutron time-of-flight experiments have been performed with an intense pulsed-neutron beam at MLF in J-PARC. Detailed analysis methods and deduced uncertainties for capture and total cross-section measurements are presented using an example of the experiments of 243Am. The deduced uncertainties are categorized into five types.

The neutron capture cross-section of 241Am was measured from 10 meV to about 500 keV using the NaI(Tl) spectrometer of the Accurate Neutron-Nucleus Reaction Measurement Instrument (ANNRI) beamline in the Materials and Life Science Experimental Facility (MLF) of the Japan Proton Accelerator Research Complex (J-PARC). The total energy detection principle was applied in conjunction with the pulse-height weighting technique to derive the neutron capture yield. The present cross-section results were normalized using a 197Au sample measurement by applying the saturated resonance method. The thermal cross section was measured to be 708 ± 22 b, in agreement with the evaluation in JENDL-5 of 709 b within uncertainties. In the keV region, the evaluated libraries of JENDL-5, ENDF/B-VIII.0 and JEFF-3.3 are in good agreement with the present results over 10 keV but show values lower by 30% to 70% below that energy. Moreover, the results of a resonance shape analysis of the resolved resonance region are also provided in the present paper. [ABSTRACT FROM AUTHOR]

Neutron total and capture cross sections of Lanthanum(La)-139 were measured at the Accurate Ne-utron-Nucleus Reaction measurement Instrument (ANNRI) of the Materials and Life Science Experimental Facility (MLF) in the Japan Proton Accelerator Research Complex (J-PARC). The total cross section was deduced from transmission measurement using a Li-glass detector in the energy range from 0.5 to 1500 eV, and the capture cross section was measured by a NaI detector in the energy range from 0.5 to 74 eV. The total cross section was largely different from that in evaluated libraries, such as JENDL-5, in the energy range from 80 to 900 eV. Resonance parameters for four resonances including one negative resonance were obtained using a resonance analysis code, REFIT. The resonance analysis revealed discrepancies in several resonance parameters with the evaluated libraries. Furthermore, the information about the scattering radius was also extracted from the results of the total cross section. The obtained scattering radius was larger than that recorded in the evaluated libraries. [ABSTRACT FROM AUTHOR]

Available nuclear data for molybdenum included in the nuclear data libraries are not of sufficient quality for reactor physics or criticality safety issues and indeed information about uncertainties and covariance is either missing or leaves much to be desired. Therefore, IRSN and JAEA performed experimental measurements on molybdenum at the J-PARC (Japan Proton Accelerator Research Complex) facility in Japan. The aim was to measure capture cross section and transmission of natural molybdenum at the ANNRI (Accurate Neutron-Nucleus Reaction measurement Instrument) in the MLF (Material Life and science Facility) of J-PARC. The measurements were performed on metallic natural molybdenum samples with various thicknesses. A NaI detector, placed at a flight-path length of about 28 m, was used for capture measurements and a Li-glass detector (flight-path length of about 28.7 m) for transmission measurements. Following the data reduction process, the measured data are being analyzed and evaluated to produce more accurate cross sections and associated uncertainties.

The neutron capture-cross section of 237Np was measured using the Accurate Neutron-Nucleus Reaction Measurement Instrument (ANNRI) with special emphasis in the region of interest for the core design of Accelerator-Driven Systems (ADS), from 0.5 to 500 keV. A neutron time-of-flight method was employed using the NaI(Tl) spectrometer in the ANNRI beamline at the Japanese Proton Accelerator Research Complex (J-PARC) together with the pulse-height weighting technique. The cross-section was determined by normalizing the results to JENDL-4.0 cross-section data at the first resonance of 237Np. In the 0.5 to 500 keV range, the present preliminary results present better agreement with previous experiments of Weston et al [3]. Experimental data from Esch et al [6] is about 15% lower than the present results. In comparision with evaluated data, ENDF/B-VIII.0 offers better agreement from 0.5 to 10 keV than with JENDL-4.0. From 0.5 to 10 keV JENDL-4.0 underestimates the present results by 10-15%. Nontheless, over 10 keV energy JENDL-4.0 shows good agreement up to 500 keV. The present preliminary cross-section has uncertainties of about 5% from 0.5 to 35 keV, a value lower than the uncertainties present in JENDL-4.0 of 6-10%. However, over 35 keV the total uncertainties steadily increase and amount to 10% at 500 keV.

In order to develop an evaluation method of gamma-ray strength function (GSF), neutron capture pulse-height (PH) spectrum of gold was employed, where it was measured with the NaI(Tl) spectrometer of AN-NRI installed at the Material and Life Science Experimental Facility in J-PARC. The neutron capture gamma-ray spectrum of gold was calculated using the nuclear reaction model code CCONE. In order to obtain the information on GSF from the measured data, a gamma-ray response function for the NaI(Tl) spectrometer was calculated by the Monte-Carlo particle-transport simulation code PHITS. As a result, the PH spectrum comparable with measured one was derived by applying the gamma-ray response function to the calculated gamma-ray spectrum. By evaluation with measured PH spectra, we obtained GSF which reasonably explains measured PH spectrum in the continuum region.

Neutron capture and total cross sections of 155Gd and 157Gd were measured with the neutron time-of-flight method in Accurate Neutron-Nucleus Reaction measurement Instrument at Material and Life Science Experimental Facility of the Japan Proton Accelerator Research Complex using the NaI (Tl) spectrometer and Li-glass detectors. Preliminary cross sections were obtained in the neutron energy region from 4 meV to 100 meV. The derived cross sections agree with evaluated values in JENDL 4.0 and the experimental results by Mastromarco but were not consistent with those by Leinweber.

A research project entitled "study on accuracy improvement of fast-neutron capture reaction data of long-lived MAs for development of nuclear transmutation systems" is ongoing as a joint collaboration, including Tokyo Tech, Japan Atomic Energy Agency and Kyoto University in Japan. This project focuses on neutron capture reaction of minor actinides 237Np, 241Am and 243Am, in the fast neutron energy region. The final goal of this project is to improve the neutron capture cross sections utilizing a high-intensity neutron beam from a spallation neutron source of the Japan Proton Research Complex. The overview of the project and the current progress are presented.