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The state-selective dissociation dynamics for anionic and excited neutral fragments of gaseous SiCl 4 following Cl 2p and Si 2p core-level excitations were characterized by combining measurements of the photoninduced anionic dissociation, x-ray absorption and UV/visible dispersed fluorescence. The transitions of core electrons to high Rydberg states/doubly excited states in the vicinity of both Si 2p and Cl 2p ionization thresholds of gaseous SiCl 4 lead to a remarkably enhanced production of anionic, Si − and Cl − , fragments and excited neutral atomic, Si * , fragments. This enhancement via core-level excitation near the ionization threshold of gaseous SiCl 4 is explained in terms of the contributions from the Auger decay of doubly excited states, shake-modified resonant Auger decay, or/and post-collision interaction. These complementary results provide insight into the state-selective anionic and excited neutral fragmentation of gaseous molecules via core-level excitation.

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The mobility-lifetime products ( μτ) and interface property have been examined through the photovoltaic studies in actual hydrogenated amorphous silicon (a–Si:H) p–i–n junction solar cells. A small amount of boron atoms included in a–Si:H enhances the μτ products of both electrons and holes up to the order of 10−7 cm2/V, which corresponds to the carrier diffusion length in excess of 5000 Å. The doped window layer possessing inferior photoelectric property works as the recombination region for photocarriers generated in the active i layer, and practically dominates the interface property together with the surface recombination velocity S0 at the electrode/doped layer interface. The S0 at the SnO2/p a–Si:H interface is estimated to be about 3×102 cm/s with an assumption of the electron mobility at 0.1 cm2/Vs. Prolonged light exposure causes a reversible change of the μτ products in every layer composing the p–i–n junction. These experimental results are discussed in connection with photovoltaic performances.

The gyrosynchrotron spectra are computed in a nonuniform magnetic field case, taking into account the self-and gyroresonance absorption. It is found that the peak frequency ν p of the gyrosynchrotron spectrum systematically increases with the increasing photosphere magnetic field strength B 0 and increasing viewing angle θ. It is also found for the first time that there are good positive linear correlations between ν p and B 0 , and between log ν p and log θ, with linear correlation coefficient 0.99 between ν p and B 0 and 0.95 between log ν p and log θ. We apply the correlations to analyze two burst events observed with OVSA and find that the evolution tendencies of the photosphere magnetic field strength B 0 estimated from the above expression are comparable with the observational results of SOHO/MDI. We also give a comparison of the diagnostic results of coronal magnetic field strength in both uniform and nonuniform source models.