Tokyo Institute of Technology

About: Tokyo Institute of Technology is a education organization based out in Tokyo, Tôkyô, Japan. It is known for research contribution in the topics: Thin film & Catalysis. The organization has 46775 authors who have published 101656 publications receiving 2357893 citations. The organization is also known as: Tokyo Tech & Tokodai.

Electron-Diffraction Study of Liquid-Solid Transition of Thin Metal Films

Abstract: Structure changes of thin films of Pb, Sn and Bi at various temperatures has been studied by electron diffraction method. The films were prepared, in the electron diffraction camera by evaporating the metals, on cleavage surfaces of several kinds of crystals. The mean thickness of the films ranged from 10A to 1000A. The observed melting points are found to be lower than those of bulk metals. Anticipating this effect to be attributed to the small size of the crystal, the author has calculated the melting temperature as a function of crystal size. The observed values of the lowering of the melting point agree fairly well with the calculated values for the crystal sizes estimated from the mean thickness and the breadth of the Debye-Scherrer rings in diffraction patterns. On cooling, the films are supercooled down to considerablly lower temperatures which can be ascribed to the slowness of the rate of nucleation in a small crystal.

Elliptic flow of identified hadrons in [formula presented] collisions at [formula presented]

Abstract: The anisotropy parameter (v(2)), the second harmonic of the azimuthal particle distribution, has been measured with the PHENIX detector in Au+Au collisions at roots(NN)=200 GeV for identified and inclusive charged particle production at central rapidities (eta 2 GeV/c, in marked contrast to the predictions of a hydrodynamical model. A quark-coalescence model is also investigated.

Monte Carlo Simulator and Ancillary Response Generator of Suzaku XRT/XIS System for Spatially Extended Source Analysis

Abstract: We have developed a framework for the Monte-Carlo simulation of the X-Ray Telescopes (XRT) and the X-ray Imaging Spectrometers (XIS) onboard Suzaku, mainly for the scientific analysis of spatially and spectroscopically complex celestial sources. A photon-by-photon instrumental simulator is built on the ANL platform, which has been successfully used in ASCA data analysis. The simulator has a modular structure, in which the XRT simulation is based on a ray-tracing library, while the XIS simulation utilizes a spectral “Redistribution Matrix File” (RMF), generated separately by other tools. Instrumental characteristics and calibration results, e.g., XRT geometry, reflectivity, mutual alignments, thermal shield transmission, build-up of the contamination on the XIS optical blocking filters (OBF), are incorporated as completely as possible. Most of this information is available in the form of the FITS (Flexible Image Transport System) files in the standard calibration database (CALDB). This simulator can also be utilized to generate an “Ancillary Response File” (ARF), which describes the XRT response and the amount of OBF contamination. The ARF is dependent on the spatial distribution of the celestial target and the photon accumulation region on the detector, as well as observing conditions such as the observation date and satellite attitude. We describe principles of the simulator and the ARF generator, and demonstrate their performance in comparison with in-flight data.