With the advancement of high-luminosity accelerator experiments, future hadron collider projects following the LHC are expected to require tracking detectors with radiation tolerance approximately ten times greater than the level at the high-luminosity LHC. Therefore, the development of semiconductor detectors capable of stable operation in such high-radiation environments is crucial to...
In nuclear medicine, there is a growing need for imaging systems capable of visualizing gamma rays in the several-hundred keV range. One notable application is the imaging of radioactive gold nanoparticles, which emit 412-keV gamma rays. Although considered promising drug carriers, their biodistribution is not fully understood, making it important to visualize their distribution in animal...
Photon-counting computed tomography (PCCT) is a next-generation medical imaging technology that acquires spectral information by counting individual X-ray photons using energy thresholds. Current commercial PCCT systems use semiconductor detectors such as CdTe and CZT. Although, these detectors provide high energy resolution, they are limited by high cost and a lack of material flexibility....
Waseda University and Science Tokyo are jointly developing GRAPHIUM, a 65 kg small satellite scheduled for launch in 2027. Its primary instrument, INSPIRE, is a box-type hybrid Compton camera operating in pinhole mode from 30 to 200 keV and Compton mode from 200 keV to 3 MeV. It achieves an angular resolution of 7.0°and an energy resolution of 7.5% at 662 keV, with an expected sensitivity...
AstroPix is a novel high-voltage monolithic active pixel sensor being developed mainly for future gamma-ray space telescope, AMEGO-X. It is also expected to be used in the barrel imaging calorimeter in the ePIC electron-iron collider detector, USA. AstroPix has to be 500 μm thick and to be fully depleted by supplying bias voltage. The energy resolution must be < 10% (FWHM) at 122 keV and the...
X-ray polarization provides unique insights into the geometry, magnetic field configuration, and emission mechanisms of high-energy astrophysical sources. While missions such as PoGO+, Hitomi/SGD, XL-Calibur, and NASA’s IXPE have demonstrated the scientific potential of X-ray polarimetry, there remains a need for instruments capable of simultaneous imaging, spectroscopy, and polarimetry with...
SiPMs (MPPCs) have a <1cm small size with a low operation voltage <~50 V, which are suitable for radiation detectors onboard satellites with the limited space and power. However, after the radiation damage of 10 Gy/year caused by cosmic-rays, the SiPM dark current increases several orders of magnitude. In this presentation, we investigated the decrease of the dark current of radiation-damaged...
