Deexcitation Dynamics of Muonic Atoms Revealed by High-Precision Spectroscopy of Electronic K X Rays.

We observed electronic K x rays emitted from muonic iron atoms using superconducting transition-edge sensor microcalorimeters. The energy resolution of 5.2 eV in FWHM allowed us to observe the asymmetric broad profile of the electronic characteristic Kα and Kβ x rays together with the hypersatellite K^{h}α x rays around 6 keV.

Proposed Cesium-free Mineralization Method for Soil Decontamination: Demonstration of Cesium Removal from Weathered Biotite.

The removal possibility of sorbed Cs from weathered biotite (WB), which is considered a major Cs adsorbent in the soil of Fukushima, has been investigated by the addition of an NaCl-CaCl mixed salt powder with a 1:1 ratio of Na and Ca and subsequent heat treatment under a reduced pressure of 14 Pa. X-ray fluorescence analysis was used to determine the Cs removal rate at elevated temperatures. The structural changes and new phases formed were determined using powder X-ray diffraction as well as electron diffraction and X-ray microanalysis in a transmission electron microscope.

Mechanism of Cs Removal from Fukushima Weathered Biotite by Heat Treatment with a NaCl-CaCl Mixed Salt.

An in situ extended X-ray absorption fine structure (in situ EXAFS) spectroscopic analysis at high temperature was conducted to investigate the mechanism of Cs removal from weathered biotite (WB) from Fukushima, induced by heating with a mixed salt of NaCl and CaCl. This indicated that most Cs remained in WB during heating at 200-700 °C. In addition, the in situ EXAFS spectra gradually changed on heating with the mixed salt and a completely different spectrum was observed for the sample after cooling from 700 °C to room temperature (RT).