Dear Brian,
Thank you so much!
We took electron mirror images when electrostatic deflector turning off and on.
Electrostatic Deflector OFF (You see L-type, normal, H-type crystals from 12 o'clock in clockwise direction.)
![](https://probesoftware.com/smf/gallery/736_14_12_21_8_35_33.jpeg)
Electrostatic Deflector ON
![](https://probesoftware.com/smf/gallery/736_14_12_21_8_34_49.jpeg)
So the problem of our PETJ and PETL crystals is not due to static filter, as Brian said.
Also as Brian noted earlier, the peak count is about 30% lower than that obtained from other lab.
Next try is to replace counters and get the Si spectra again.
=> As expected, this issue is not related to counter.