A kHz heat‐load shutter for white‐beam experiments at synchrotron sources

A heat‐load shutter capable of frequencies from one to several tens of kHz and window times from 10 µs up to 1 ms is described. In the current configuration the water‐cooled shutter absorbs ～99% of the heat generated by the white beam. It has been successfully used for extended periods synchronized with a Jülich pulse‐selector operating at 946 Hz. The temperature of the pulse‐selector remained constant during a three‐day continuous operation. Flexibility is provided by the interchangeability of the chopper disc.     

A plug‐and‐measure diagnostic tool for flux,resolution and beam size of a soft X‐ray beamline

A compact multi‐functional diagnostic tool has been installed for commissioning beamlines at the Taiwan Light Source. For a photon beam, the instrument can measure the photon flux, energy resolution and beam size, consecutively with a photodiode or gold mesh, a windowless gas cell and a movable fluorescence screen viewport. Two gratings with ruling densities of 350 and 1000 lines mm^?1 and dispersing photons of energies from 80 to 1200 eV were calibrated with a photon flux of 10¹¹ photon s^?1 at slit openings of 50 µm × 50 µm; a maximum resolving power of greater than 10000 was certified with an absorption spectra of gaseous samples. Pressure differences over four orders of magnitude were achieved between the ion chamber and the flux measurement chamber with a single capillary differential pumping stage. A sequence of beam profiles was measured by moving continuously in the vicinity of the nominal focal positions. This tool is useful in commissioning or trouble‐shooting at most beamlines in a synchrotron facility.