Simulation results of a New type of sandwich calorimeter, Double readout Sandwich Calorimeter (DSC) performance

In this study, we propose a novel fully active total absorption calorimeter with enhanced read out capabilities through fine splitting. The proposed calorimeter employs a sandwich structure composed of scintillator glasses and lead glasses, which are subdivided into small tiles. This configuration enables the creation of a finely segmented three-dimensional calorimeter that is compatible with Particle Flow Algorithms (PFA). This article presents a comprehensive description of the calorimeter design and reports performance results obtained through simulations. Notable, calorimeter demonstrates exceptional linearity and energy resolution, closely rivaling that of homogeneous calorimeters. The simulated calorimeter achieves an impressive energy resolution of approximately $9\% / \sqrt{E(\textrm{GeV})}$

Magnesium-Based Materials for Hydrogen Storage: Microstructural Properties

Magnesium (Mg) is hydrogenated as core-shell-type hydride. Therefore, increase of absorption capacity to the theoretical hydrogen capacity is still one of the most important issues for the hydrogen storage materials. In this study, the procedure of the core-shell structure as well as effect of Al concentration in Mg on the growth MgH2 in Mg were investigated. MgH2 was formed on the surface as well as inside of unreacted Mg core. The inside MgH2 was formed in a granular form on Mg grain boundary and its size increased by applying plastic deformation. Thickness of the surface MgH2 and size of the internal MgH2 increased with an increase in hydrogenation time until the hydride surface was completely covered with MgH2. However, the growth of the surface and internal MgH2 came to a halt after the surface was covered with MgH2. From these results, supplying H from metal side was dominantly contributed for growth of the surface and internal MgH2 because diffusion rate of H in Mg was much higher than that in MgH2. In addition, the growth of internal MgH2 as well as control of surface MgH2 can contribute to the promotion of the complete hydrogenation of Mg-based hydrogen storage materials

Next-generation PET capability with lutetium fine silicate and multi-pixel photon counter

Currently, positron emission tomography (PET) systems are rapidly developing owing to the invention of new scintillators and photosensors, which contribute to construction of clearer and high-resolution images in cancer diagnosis. In this study, we used a Lutetium Fine Silicate (LFS) inorganic scintillator and multi-pixel photon counter (MPPC) as a photosensor. This combination is realistic for next-generation PET systems. These devices were directly coupled to form a unit detector. A pair of detector units was placed face-to-face, and they simultaneously detected annihilation gamma rays, assuming a pair detector in the PET system. A timing resolution of 96 ps in full width at half maximum (FWHM) was obtained. This result is almost the fastest timing resolution ever achieved. A good timing resolution contributes to noise reduction that leads to clear images. Furthermore, a spatial resolution of 1.9 mm in FWHM was obtained, which is sufficient to meet the spatial resolution requirements for next-generation PET systems.ArticleJOURNAL OF INSTRUMENTATION. 7:P10014 (2012)journal articl

Measurement on properties of MPPC for TOF-PET system

A large number of techniques are rapidly being developed for the diagnosis of cancer, including time-of-flight positron-emission tomography (TOF- PET). To construct an effective TOF-PET system, we introduced lutetium fine silicate (LFS) as a scintillator and a multi-pixel photon counter (MPPC) as a photosensor that exhibits a rapid response. In this study, we investigated four types of MPPCs with a sensitive area of 1 x 1 mm(2) sensitive area and different pitch sizes. All MPPCs showed a timing resolution of 72 ps at the full-width at half-maximum with operating voltages of dV similar to 3 V (with the exception of the 100-pixels MPPC).ArticleJOURNAL OF INSTRUMENTATION. 8:P02018 (2013)journal articl