This year has seen significant improvements in X-9B hardware and software as a new computer system has been purchased, tested, and installed to replace the aging PDP-11 system. This is the first major computer improvement in the beamline in over 12 years. The new system is CAMAC compatible, utilizes LabView for programming (with its easy to use graphical programming) on a Gateway Pentium PC under Windows 95. This has increased data storage, speed, networking capability, and compatibility with other computer systems significantly. The stability and reproducibility of the intensity of the dynamically focused x-ray beam from the sagittally focusing monochromator has been significantly improved. Also, data collection during scanning has been enabled by angling the trolley rail so that focus is maintained during an energy scan. Increased stability was also achieved by counter balancing the massive crystal bender about its rotation axis, and thereby reducing the dispersion of the Piezo voltage with energy (the piezo keeps the first and second crystals of the double crystal monochromator aligned). New software parameters were then determined for the equation of motion for the monochromator and for the piezo calibration routine. Thus, the automatic piezo calibration software that has been used with the nonfocusing monochromator can be used with the sagittal focusing monochromator. The new software parameters also restore the constant exit height feature of the monochromator for energy ranges on the order of 1000 eV. Thus after initially focusing the beam, the dynamically focusing feature of the monochromator is transparent to the user.
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