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A unique analytical method is proposed for local structure analysis via extended X-ray absorption fine structure (EXAFS) spectroscopy. The measurement of electron energy distribution curves at various excitation photon energies using an electron energy analyzer is applied to determine a specific elemental Auger spectrum. To demonstrate the method, the N K-edge EXAFS spectra for a silicon nitride film were obtained via simultaneous measurement of the N KLL Auger and background spectra using dual-energy windows. The background spectrum was then used to remove the photoelectrons and secondary electron mixing in the energy distribution curves. The spectrum obtained following this subtraction procedure represents the `true' N K-edge EXAFS spectrum without the other absorptions that are observed in total electron yield N K-edge EXAFS spectra. The first nearest-neighbor distance (N-Si) derived from the extracted N K-edge EXAFS oscillation was in good agreement with the value derived from Si K-edge analysis. This result confirmed that the present method, referred to as differential electron yield (DEY)-EXAFS, is valid for deriving local surface structure information for low-Z elements.

The Drude tail due to photo-excited carriers in single-walled carbon nanotubes (SWNTs) has been observed in the mid-infrared region by using combination spectroscopy of synchrotron radiation and Ti:sapphire laser. It is found that the density of photo-excited carriers increases as the sample temperature is raised from 12 to 300 K, and their lifetime is of the order of minutes at 300 K. These facts suggest that the movement of photo-excited carriers is largely affected by some extrinsic defect, thus resulting in the long-lasting Drude reflection in SWNTs.

A new spherical-grating monochromator with translational and rotational assembly including a normal-incidence mount (SGM-TRAIN) has been constructed at BL5A of the UVSOR facility. The SGM-TRAIN is an advanced version of a constant-length SGM with the following improvements: (i) a wide energy range of 5-250 eV; (ii) a high resolving power; (iii) use of linear and circular polarization; (iv) reduction of second-order light; (v) two computer-controlled driving modes. Part of the performance tests are reported along with a detailed description of the design.

A helical undulator was installed in the 0.75 GeV storage ring of the UVSOR facility of the Institute for Molecular Science. The undulator was designed to produce the fundamental of the circularly polarized undulator radiation in the energy range 2-43 eV, and the higher harmonics with elliptical polarization in the energy range up to 300 eV. Recently, the first spectrum from the undulator was observed. The performance of the undulator and the obtained spectrum are reported.