The final major component of the endstation, the detector array, is now installed. Four silicon drift detectors are positioned 30 mm from the sample with a specific geometry that will provide multiple perspectives and optimize contrast. 3D printed caps are positioned over the detectors to prevent damage, reduce scattering background and hold thin film filters.
Test measurements were made of a fly wing. Images of a 2 x 2 mm field of view were acquired at a resolution of approximately 20 microns. The lower image shows x-ray transmission and the upper image shows carbon fluorescence. An x-ray energy of 290 eV was used in the acquisition.
The first x-ray images have been acquired on the SGM. The test samples were a 0-80 nut and a gold mesh with a wire pitch of 20 microns. A photon energy of 711 eV (Fe L-edge) was used and the total electron yield from the sample was used to generate the contrast in the images.
The KB mirrors have been successfully used to focus the beam to approximately 30 x 20 microns. Optimization of the transmission and the beam demagnification will continue.
The two 150 mm long trapezoidal focussing mirrors were successfully installed on July 23rd. Bending motors and encoders have been tested.
Testing of the KB mirror bender mechanism and motors is underway. This system is 375 mm upstream from the sample and will focus the beam to 10 by 10 microns.
The ambient pressure endstation sample holders have been prototyped. This particular sample holder will accommodate 22 samples and was designed for soils and sediments.
The vacuum compatible hexapod sample positioner has been installed and tested in the ambient pressure endstation.
The Spherical Grating Monochromator (SGM) beamline is a soft x-ray beamline located at the Canadian Light Source. The beamline is equipped with two in-line endstations that can be used for high resolution x-ray absorption spectroscopy and photoelectron spectroscopy. The first endstation is maintained at ultra high vacuum and houses a Scienta SES-100 photoelectron spectrometer and a single silicon drift detector. The second endstation (currently under construction) is capable of operation at ambient pressures and uses an array of silicon drift detectors for measurement of partial fluorescence yields. The beam is focussed to 10 microns in this endstation for x-ray fluorescence mapping of light elements.
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