Hokkaido University

About: Hokkaido University is a education organization based out in Sapporo, Hokkaidô, Japan. It is known for research contribution in the topics: Population & Catalysis. The organization has 53925 authors who have published 115403 publications receiving 2651647 citations. The organization is also known as: Hokudai & Hokkaidō daigaku.

Dispersion relation and optical transmittance of a hexagonal photonic crystal slab

Abstract: The dispersion relation and the optical transmittance of a two-dimensional photonic crystal composed of the hexagonal array of cylindrical air holes fabricated in a dielectric slab were analyzed by group theory and the numerical calculation based on the finite-difference time-domain method. The decay rate of the leaky modes that exist above the light line (the dispersion relation in air) in the band diagram was also evaluated, from which the absence of the coupling between certain internal eigenmodes and the external radiation field was shown. This phenomenon was related to symmetry mismatching by the group-theoretical argument. It was also shown that a certain leaky band has a quality factor as large as 3000 over its entire spectral range. These features as well as the opaque frequency regions due to symmetry mismatching were clearly demonstrated by the calculated optical transmission spectra.

Relativistic nuclear collisions at 10A GeV energies from p+Be to Au+Au with the hadronic cascade model

Abstract: A hadronic cascade model based on resonances and strings is used to study mass dependence of relativistic nuclear collisions from p+Be to Au+Au at AGS energies ({approx}10A GeV) systematically. Hadron transverse momentum and rapidity distributions obtained with both cascade calculations and Glauber-type calculations are compared with experimental data, leading to a detailed discussion concerning the importance of rescattering among hadrons. We find good agreement with the experimental data without any change of model parameters with the cascade model. It is found that rescattering is of importance both for the explanation of the high transverse momentum tail and for the multiplicity of produced particles. (c) 1999 The American Physical Society.