4-3 Detector:  Hitachi Hitech 7-element Vortex Silicon drift diode (SDD) detector

4-3 detector counting electronics: Quantum Detectors Xspress3X box

4-3 Xspress3X server computer address: 192.168.43.7


NOTE: Even though the program is called, WebGe, it works with SDD detectors too!


Count rate limitations to avoid deadtime effects at 4-3 with the Xspress3 electronics and 7-element Vortex detector:

ICR < 500,000 counts per channel

SCA1, SCA2 < 60,000 counts per channel


  1. From the Data Collector window, click on the three-line icon (hamburger/stack of pancakes button) in the upper right hand part of the window → WebGe
  2. A new tab will open up on your browser which has the WebGe interface:
  3. Troubleshooting: If you are getting an initialization error or other errors upon opening WebGe, then the WebGe program's connection to the Xspress3 server may be down.  Please see the Connecting to the Xspress3 detector electronics server page.
  4. In the “Statistics” box on the left of the screen, press “Count All”. Look at the ICR values being reported. If they are too high (>500,000 on average for fast Xspress3 and Vortex electronics), decrease the beam size or move the detector farther back.
  5. Check for previously saved SCA files for the element you are measuring. Access saved SCA files by clicking the hamburger button → File → Open SCA. You or your research group may already have SCA files in the User folder. If not, select Master and search the filenames for the most recent SCA for your element of interest. Files exist for S through Zn K alpha and beta fluorescence (alpha is SCA1, beta is SCA2).
  6. Immediately after loading an SCA file, press the Update DXPs button to send the current window values to the Xspress3 electronics.  If this is not done, the detector will window to whatever it was set to last which might be random!
  7. At the bottom of the page, enter the element of interest to view its alpha and beta fluorescence energies.
  8. In the “Detector Geometry” box, select the element you want to window (1-7).
  9. At the top open the shutter. In the “MCA Control” box, press start. You should see the full spectrum in the bottom graph. Click and drag to zoom in on a certain portion in the larger graph. You may be able to see several peaks: Kalpha, Kbeta, scattered beam, harmonic of scattered beam.
  10. Zoom in on the Kalpha and Kbeta peaks. Introduce a window by checking the box next to SCA 1, in the “SCA Control” box. The window is defined by its MCA channel center and width, NOT the energy. The MCA channel number is approximately 1/10 of the energy of the fluorescence peak in eV. If you click at a point in the spectrum in the Zoom window, the Energy and MCA channel of that point are displayed in the bar above the window.
  11. Note: Select “AntiCoinc” at the bottom to see how the window is cutting out the fluorescent signal. Select “Coinc” to see just the signal within the window. It is generally most useful to window in AntiCoinc mode.
  12. Adjust the window center and width on the SCA 1 channel. You want the window to cut out the region slightly to the left of the center of the Kalpha peak.
    *** Channels in detector geometry will turn red if ICRs are too high. If you notice this, make adjustments either to detector distance or beam size to lower the ICR values.
  13. With the SCA1 channel box checked, click the "Apply to All" button to copy the SCA settings for the current detector channel to all 7 Vortex channels.
  14. The fluorescence spectra are pre-calibrated by the Xspress3 setup software to be very similar to each other in terms of bin position.   Still, it is important to click on each channel to make sure this is true!
  15. Continue adjusting windows for each element (Step 9).
  16. When finished, go to the triple bars () at the top right → File →  Save SCA →  Save the file name (usually something like: [Metal]_MonthYear.sca). Save to User.
  17. Immediately after saving the SCA file, press the Update DXPs button to send the current window values to the Xspress3 electronics.  If this is not done, the detector will window to whatever it was set to last which might be a non-optimized window!
  18. The 7-element Vortex detector should be windowed for each element of interest in your samples before collecting data at that element's absorption edge.
  19. When finished windowing, Open the window file to ensure that it is active (Triple bars → File → Open SCA), and hit Update DXPs one more time.
  20. Count rate limitations to avoid deadtime effects at 4-3 with the Xspress3 electronics and 7-element Vortex detector:
    1. ICR < 500,000 counts per channel
    2. SCA1, SCA2 < 60,000 counts per channel
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