EXFOR-based simultaneous evaluation for neutron-induced fission cross section of plutonium-242

The $^{242}$Pu neutron-induced fission cross section was evaluated from 100 keV to 200 MeV. The experimental $^{242}$Pu and $^{235}$U fission cross sections and their ratios in the EXFOR library were reviewed and analysed by the least-squares method. Additional simultaneous evaluation was performed by including the experimental database of the $^{233,238}$U and $^{239,240,241}$Pu fission cross sections and their ratios developed for JENDL-5 evaluation. The $^{242}$Pu fission cross sections from our evaluation and JENDL-5 evaluation are close to each other below 1 MeV while systematically differ from each other above 10 MeV. The cross section from our evaluation is systematically lower than the JENDL-4.0 cross section in the prompt fission neutron spectrum peak region ($\sim$5% lower around 1 MeV). The newly evaluated $^{242}$Pu fission cross section was verified against the cross section measured in the $^{252}$Cf spontaneous fission neutron field and criticalities of small-sized LANL fast systems, and demonstrated better performance than the JENDL-4.0 cross section on the same level with the JENDL-5 cross section.Comment: Submitted to Journal of Nuclear Science and Technolog

Spin-dependent observables in surrogate reactions

Observables emitted from various spin states in compound U nuclei are investigated to validate usefulness of the surrogate reaction method. It was found that energy spectrum of cascading $\gamma$-rays and their multiplicities, spectrum of evaporated neutrons, and mass-distribution of fission fragments show clear dependence on the spin of decaying nuclei. The present results indicate that they can be used to infer populated spin distributions which significantly affect the decay branching ratio of the compound system produced by the surrogate reactions

Analysis of proton-induced fragment production cross sections by the Quantum Molecular Dynamics plus Statistical Decay Model

The production cross sections of various fragments from proton-induced reactions on $^{56}$Fe and $^{27}$Al have been analyzed by the Quantum Molecular Dynamics (QMD) plus Statistical Decay Model (SDM). It was found that the mass and charge distributions calculated with and without the statistical decay have very different shapes. These results also depend strongly on the impact parameter, showing an importance of the dynamical treatment as realized by the QMD approach. The calculated results were compared with experimental data in the energy region from 50 MeV to 5 GeV. The QMD+SDM calculation could reproduce the production cross sections of the light clusters and intermediate-mass to heavy fragments in a good accuracy. The production cross section of $^{7}$Be was, however, underpredicted by approximately 2 orders of magnitude, showing the necessity of another reaction mechanism not taken into account in the present model.Comment: 12 pages, Latex is used, 6 Postscript figures are available by request from [email protected]

Anaemia, iron deficiency and vitamin A status among school-aged children in rural Kazakhstan.

OBJECTIVES: To investigate the prevalence of anaemia and iron deficiency and vitamin A status among school-aged children in rural Kazakhstan and identify factors associated with anaemia in this population. DESIGN: A cross-sectional design. SETTING: School-aged children in rural Kazakhstan. SUBJECTS: Socio-economic and anthropometric information was collected from 159 school-aged children living in the Kzyl-Orda region of Kazakhstan. Blood samples were collected and the concentrations of haemoglobin (Hb), serum iron, serum ferritin (SF), erythrocyte protoporphyrin (EP), serum retinol and beta-carotene, total iron binding capacity (TIBC), transferrin saturation (TS) and other haematological indices were measured. RESULTS: Among the 159 children, the prevalence of anaemia and iron deficiency defined by the multiple criteria model (SF, TS and EP) was 27% and 13%, respectively. Nine per cent had iron-deficiency anaemia and 21% had serum retinol value < 1.05 micromol l(-1). Mean SF and serum iron concentrations and TS were significantly lower in anaemic children than in their non-anaemic peers, while TIBC and EP were significantly higher in children with anaemia. Hb was significantly correlated with serum iron and retinol concentrations. Serum retinol and SF concentrations and mean corpuscular volume were significantly correlated with Hb by multiple regression analysis. CONCLUSIONS: Anaemia among school-aged children in rural Kazakhstan appears to be related to iron indices and vitamin A status

Measurement of a Phase of a Radio Wave Reflected from Rock Salt and Ice Irradiated by an Electron Beam for Detection of Ultra-High-Energy Neutrinos

We have found a radio-wave-reflection effect in rock salt for the detection of ultra-high energy neutrinos which are expected to be generated in Greisen, Zatsepin, and Kuzmin (GZK) processes in the universe. When an UHE neutrino interacts with rock salt or ice as a detection medium, a shower is generated. That shower is formed by hadronic and electromagnetic avalanche processes. The energy of the UHE neutrino shower converts to thermal energy through ionization processes. Consequently, the temperature rises along the shower produced by the UHE neutrino. The refractive index of the medium rises with temperature. The irregularity of the refractive index in the medium leads to a reflection of radio waves. This reflection effect combined with the long attenuation length of radio waves in rock salt and ice would yield a new method to detect UHE neutrinos. We measured the phase of the reflected radio wave under irradiation with an electron beam on ice and rock salt powder. The measured phase showed excellent consistence with the power reflection fraction which was measured directly. A model taking into account the temperature change explained the phase and the amplitude of the reflected wave. Therefore the reflection mechanism was confirmed. The power reflection fraction was compared with that calculated with the Fresnel equations, the ratio between the measured result and that obtained with the Fresnel equations in ice was larger than that of rock salt.Comment: 6 Pages, 5th International Workshop on Acoustic and Radio EeV Neutrino Detection Activitie