The present paper reports the X-ray detector projects undertaken at the SPring-8 facility, which are (1) Multiple CCD X-ray Detector Project, (2) MicroStrip Gas Detector Project, and (3) Advanced Ionization Chamber Project. These projects are to develop novel detectors with which the synchrotron radiation community could fully appreciate the high brilliance, the high flux or the high energy of the X-ray beams provided by the third generation of synchrotron radiation facility.

  Undulators of a new type proposed and developed in the Electrotechnical Laboratory which produces polarized radiation of any ellipticity are installed in the electron storage rings TERAS and NIJI-II. Circularly polarized synchrotron radiation emitted from these polarizing undulators is being used in various research fields in our laboratory. We report the radiation characteristics of the polarizing undulator, magnetic circular dicroism study for magnetic materials, absolute asymmetric synthesis study, and development of circular dicroism microscope.

  XAFS is a powerful method for structure and electronic state analyses, which can be used for not only crystalline but also non-crystalline materials under various environments. XAFS has become one of the standard analytical tools with the development of synchrotron radiation. It has enough high sensitivity to analyze solute in solutions, supported catalysts etc. Fluorescent XAFS has higher sensitivity, thus is used for the analyses of dopants in semiconductors, biological samples etc. XAFS of surface localized materials can be obtained by electron yield, conversion electron yield or total reflection fluorescence methods. Recent development of XAFS is summarized from the view point of experimental technique.

  High energy photon beams generated by Laser Compton Backscattering have been developed in Electrotechnical Laboratory for the establishment of the standard field of high energy photon, and for application of nuclear physics, etc. The principle, the characteristics of the Laser-Compton photon beam and the applications are briefly described.

  Although a number of new diagnostic imaging techniques have been developed in the past 100 years, x-rays are still necessary in modem medicine. Synchrotron radiation (SR), which is characterized by its extremely high intensity and broad-band energy spectrum, will certainly be a powerful x-ray source for further innovation in diagnostic imaging. After a brief review of the present status of medical applications of SR, a fluorescent x-ray monochromatization method, which has been developed by the authors, is described.

  A survey is given of recent progress in experimental studies of photoabsorption, photoionization, and photodissociation of molecules in the wavelength range of photons in the vacuum ultraviolet. Corresponding photon energies are 10-50eV, at which most of the optical oscillator strength of molecules are distributed. Examples of molecules chosen here are ranged from simple diatomic and triatomic molecules to polyatomic molecules such as hydrocarbons, alcohols, ethers, and some Si-containing compounds in the gas phase. A particular emphasis in the survey is placed on current understanding of the spectroscopy and dissociation dynamics of molecules in the superexcited states which are produced in the interaction of photons in this wavelength (or energy) range with molecules. A comparative survey is also given briefly of the spectroscopy and dynamics of superexcited states which are produced in electron-molecule collisions. Most of the observed superexcited states are assigned to high Rydberg states which are vibrationally (or/and rotationally), doubly, or inner-core excited, and converge to each of ion states. Non-Rydberg superexcited states are also observed.

  Utilizing the nuclear forward scattering with synchrotron radiation, material research by means of Mössbauer spectroscopy in time domain has been demonstrated. First, a brief introduction of the Mössbauer spectroscopy is presented and, second, the characteristic feature of the nuclear forward scattering (NFS) with a synchrotron radiation has been discussed. As an example for the material research, the results from a high pressure ⁵⁷Fe Mössbauer study with NFS on a perovskite-type iron oxide, SrFeO₃, using a diamond anvil cell (DAC) have been presented.

  High energy synchrotron radiation is effectual in measureing Compton profiles because of not only its high intensity but also its linear or circular polarization. Compton profiles inform us the electron momentum distribution in matter. Useful information on the electronic states in metals and alloys, particularly on the electron correlation effect on the momentum distribution have been obtained. In addition, magnetic properties have been investigated by means of the spin-dependent Compton scattering. The information of recoiled electrons is also useful to directly know the 3D momentum density of electrons. Beginning at the introduction to the Compton profile, this article reviews some resent results of Compton profiles using synchrotron radiation.

  A charge-integrating position-sensitive proportional counter (CIPSPC) has been developed for nondestructive testing using a Cu target X-ray generator. The CIPSPC consists of two anode wires and 320 signal detection electrodes with a pitch of 0.4mm. Each electrode has a storage capacitor. The charges stored in the 320 capacitors are serially read out through analog multiplexers. The image of falling freely scissors was recorded with a time resolution of 1ms as a demonstration of the application. The counting characteristics of CIPSPC are also stated.