Numéro
J. Phys. Colloques
Volume 47, Numéro C8, Décembre 1986
EXAFS and Near Edge Structure IV
Page(s) C8-139 - C8-142
DOI https://doi.org/10.1051/jphyscol:1986825
EXAFS and Near Edge Structure IV

J. Phys. Colloques 47 (1986) C8-139-C8-142

DOI: 10.1051/jphyscol:1986825

LINEAR DETECTOR FOR TIME-RESOLVED EXAFS IN DISPERSIVE MODE

H. OYANAGI1, T. MATSUSHITA2, U. KAMINAGA3 et H. HASHIMOTO4

1  Electrotechnical Laboratory, Sakuramura, Niiharigun, Ibaraki 305. Japan
2  National Laboratory for High Energy Physics, Ohomachi, Ibaraki 305, Japan
3  Rigaku Corporation, Matsubaracho, Akishima, Tokyo 196, Japan
4  Toray Research Center Inc., Sonoyama, Ohtsu, Shiga 520, Japan


Abstract
A fast read-out system for a linear photodiode detector has been developed for a time-resolved EXAFS experiment in dispersive mode. A green lightemitting phospher (Gd2O2:Tb) is deposited on a fiber optic faceplate, which is optically coupled with a linear photodiode array with 1024 sensor elements. A 12-bit fast A/D converter is used to process 1024 channel data in 5 msec and store them in memory. Digital data can be routed and stored in a histogram memory having 16 frames with 20 bits. 16 spectra can be rneasured successively with a time resolution of 5 msec and a variable interval time. An energy resolution of the total system is 5.6 eV at the Fe K-edge. for 1200 eV energy range. The application to a kinetic study demonstrates that time resolved EXAFS or near-edge spectra can be obtained with a time resolution of 25 msec by use of the present detector system.