Absolute Intensity of Soft X-Rays of Synchrotron Radiation from the ETL-Storage Ring

The absolute intensity of X-rays in synchrotron radiation from the ETL-storage ring was measured using a proportional counter with a mylar (45 Å region), aluminum (8.3 Å region) or titanium window (2.7 Å region). The measured intensities were compared with those by calculation based on Schwinger's formula. The several parameters necessary for the calculation were obtained using the measured values and data from the literature. A comparison showed that the synchrotron radiation from the ring is suitable as a standard light source in these soft X-ray regions, and it was found that absolute intensity measurements in soft X-ray regions serve as accurate diagnostics for this storage ring.