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Ron Rasch wrote:
> . . . My big problem right now spectrometer reproducibility. The
> spectrometer doesn't always go back to the correct position, giving
> me a count rate that varies by too much (eg 5% measuring the Ka of a
> pure metal). Any advice on what to check next?
About your spectrometer reproducibility issue, what have you tried,
and what are the symptoms? Is this a 8600 or 8900? Does your
spectrometer have problems at all L levels, or just high or low ones?
When moving in both directions or just one? How does peak shape
affect your drop-off (e.g., Si vs Fe)? What happens if you re-peak,
say, a hundred of times and track the L values? Any trends? What
about the counts if you repeak each time? Those okay? What happens
if you swap the stepper motor with that from another spectrometer? I
assume that the other spectrometers are functioning normally.
Manager & Principal Analyst, Electron Microprobe Lab
Senior Research Fellow, Department of Geology & Geophysics
University of Minnesota - Twin Cities