[Basic Knowledge of Neutron: Physics].

Neutrons are uncharged particles and exhibit strong ability to penetrate matter. Various charged particles and gamma rays are emitted from nuclear reactions induced by neutrons passing through the matter. It is important to consider contributions of neutrons for estimating such quantities used in radiation protection as absorbed dose, equivalent dose and effective dose.

Development and characterization of optical readout well-type glass gas electron multiplier for dose imaging in clinical carbon beams.

The use of carbon ion beams in cancer therapy (also known as hadron therapy) is steadily growing worldwide; therefore, the demand for more efficient dosimetry systems is also increasing because daily quality assurance (QA) measurements of hadron radiotherapy is one of the most complex and time consuming tasks. The aim of this study is to develop a two-dimensional dosimetry system that offers high spatial resolution, a large field of view, quick data response, and a linear dose-response relationship. We demonstrate the dose imaging performance of a novel digital dose imager using carbon ion beams for hadron therapy.

Development of a microcalorimeter with transition edge sensor for detection of LX rays emitted by transuranium elements.

A transition edge sensor (TES) microcalorimeter has been developed for use as an energy dispersive X-ray spectrometer. The TES microcalorimeter is a thermal detector that enables one to determine the energy of an incident photon by measuring the resultant increase in temperature. In this work, a Ti/Au TES microcalorimeter was developed to measure LX rays emitted by transuranium elements.

Microcalorimeter-type energy dispersive X-ray spectrometer for a transmission electron microscope.

A new energy dispersive X-ray spectrometer (EDS) with a microcalorimeter detector equipped with a transmission electron microscope (TEM) has been developed for high- accuracy compositional analysis in the nanoscale. A superconducting transition-edge-sensor-type microcalorimeter is applied as the detector. A cryogen-free cooling system, which consists of a mechanical and a dilution refrigerator, is selected to achieve long-term temperature stability.