How to take fluorescence spectra with the Ketek detector

  • open the MAD GUI
  • in general from the DA+ GUI
  • select appropriate element
  • for AUTOMATED filter selection (the program will search for optimized transmission settings) select this option, inspect the spectrum and start the scan if the values are reasonable
  • OR select the appropriate transmission manually:
  • move in an optimal amount of filters to avoid saturation and to spare your sample
    • this means:
      • maximum filters to get a signal at all (start with around 0.001 beam)
      • take a spectrum - already signal?
      • do not saturate the detector - dead time of below 20 % is ok. (5 % to 10 % good).
      • successively take out filters until good signal (peak at beam energy and at the expected line of your sample if you are ABOVE the absorption edge)
  • start the scan
  • check the calculated values of inflection and peak carefully (is the fit reasonable? "visual inspection")
  • go to the desired energies for peak and inflection etc.
    • either from the MAD GUI
    • or from the IDL session (start feedback again after changing energies)