Absolute brightness measurements at the LURE synchrotron with a bolometer and application to the absolute calibration of photodiodes and photocathodes

Abstract

An electrically calibrated bolometer designed to measure VUV and soft X-ray radiation in tokamaks was installed at the end of the calibration beam line used by CEL-V at the LURE synchrotron. Low-noise electronics and an adequate data acquisition enabled absolute measurements of power densities as low as 1 μW/cm2. Power density measurements are presented. At the same location several soft X-ray detectors used in laser-plasma interaction studies were installed and their absolute calibration was performed (photocathodes, photodiodes, etc.). Calibration results are presented and compared with a Henke model for photocathode response.