村松 康司

Spectral characterization was made on undulator radiation from a 26-period high-field permanent magnet multipole wiggler/undulator at the 2.5-GeV Photon Factory storage ring. In an undulator mode of a weaker field version of the insertion device, the K parameter was tuned up to 5.8. Absolute spectral measurement showed source brightness of the first harmonic peak in the order of 1015 photons/s mrad2 100 mA 0.1% bandwidth over the full tunable range of the first peak from 40 to 400 eV. As for the higher harmonics, spectral profile, the peak brightness, and quasimonochromaticity were obtained in this transition region where the K parameter increased beyond unity.

Formulations in a ray tracing program for simulating sychrotron radiation sources such as bending magnets, wigglers, and undulators are described. The characteristic spatial behavior of rays emitted from the sources is simply expressed in the ray tracing program by using the Box and Müller method. A ray tracing simulation of a multipole wiggler beamline, BL-16, at the Photon Factory is also described. The result indicated that the wiggler radiation was collimated vertically with the divergence of 4 arcsec by a collimating mirror and focused at the sample position with spot size of 1.5 mm×0.5 mm.

A VUV/soft x-ray monochromator was developed for utilizing undulator radiation from a 26-period multipole wiggler/undulator at the Photon Factory. An entrance slitless quasi-Rowland circle mounting was adopted to the monochromator optics, aimed at achieving the compatibility of high resolution with high-output flux. The optics was realized by a decoupling of horizontal focusing with a deflection mirror from vertical focusing with an aberration-free vertical dispersion system which was composed of a cylindrical mirror and a concave grating. The optics and mechanism of the monochromator as well as its test operation made after installation are described.

A new ray-tracing program was developed to facilitate optical design of synchrotron radiation beam lines and monochromators. The program uses Monte Carlo modelling to simulate characteristics of insertion-device sources such as undulators and wigglers as well as those of normal bending magnets. The program is successfully applied to the optical design of monochromator systems for a new multipole wiggler/undulator beam line (BL16) at the Photon Factory. © 1988 The Japan Society of Applied Physics.

Effect of the statistical Fermi level shift on the Meyer-Neldel rule of a-Si:H conductivity was studied using the temperature dependence of MOSFET conductivity. A model is presented in which the temperature dependence of surface band bending in a MOSFET should compensate for the statistical Fermi level shift of bulk a-Si:H. This compensation is verified by the SiO2 thickness dependence of the MOSFET conductivity. The pre-exponential factor obtained by analysis of the temperature dependence of MOSFET conductivity does not show the Meyer-Neldel rule. It is therefore concluded that the Meyer-Neldel rule observed in bulk a-Si:H conductivity is predominantly caused by the statistical Fermi level shift. © 1986.

HD formation reaction was investigated in H2 plasma over deuterium-incorporating hydrogenated amorphous silicon (a-Si:H:D). The activation energy of the reaction was determined to be 2.4±0.7 kcal mol-1, which was consistent with the abstraction reaction of hydrogen from some silane derivatives by hydrogen atoms. The HD formation reaction could be explained by the hydrogen abstraction reaction. The hydrogen abstraction from a-Si:H surface by H atoms is thought to be one of the elementary growing processes of an a-Si:H in a SiH4-H2 plasma.

Recoil reactions of tritium produced by 3 He (n, p)3 H in a gas phase with naphthalene and its derivatives (all solids) were investigated. It was found that intramolecular distribution of tritium was not uniform, in contrast to most of the experiments on aromatic compounds performed in the past. The non-uniformity was remarkable in strongly activated rings, and this was attributed to the ease of formation of an intermediate complex which decays to the parent type molecule tagged with tritium. The energy range of formation of the complex is supposed to be high enough to show no temperature dependence on the yield but low enough to display orientation effects in substitution reaction of hydrogen of the ring. The yields for tritium-labeled labile groups (OT and COOT) were investigated in the parent compounds. The trend of the yields could be correlated to the ring activity of aromatic compounds. An extraordinarily high yield was obtained for 1-hydroxy-2-naphthoic acid, which has intramolecular hydrogen bonding. Thermal processes may be involved in the yields of labile tritium because of their temperature dependence. © R. Oldenbourg Verlag, München 1985