¿ªÔÆÌåÓýGeo, To tell what¡¯s going on in the real low energy region you need a lot of counts to separate noise from closely spaced elements that may be separated by 100ths of a keV. Mo is 2.293, 2.395 while S is 2.308 so they are 0.015 keV apart and your channel resolution is 0.030 keV. You¡¯ll need confirming lines to be certain, but with the high percentage of Mo I¡¯d go with Mo. ?Spikes are the jagged single channel noise on the side of what should be a nice smooth Gaussian peak. Your mca file has all that data in it open it with note pad and look at the very bottom. Fast Count: 6272 Slow Count: 2176 GP Count: 0 Accumulation Time: 300.000000 Real Time: 300.294000 Dead Time: 65.31% HV Volt: 188V TEC Temp: 229K Board Temp: 46¡ãC <<DPP STATUS END>> And I wonder what that 65% is due to although it may be the LLD is set at 0, but I do see the real and live time fighting pile up so something is getting noise in there. Try setting the LLD .cut off below 0.74 keV GAIN - 3 THRESHOLD - 0 LIVE_MODE - 0 PRESET_TIME - 0 LIVE_TIME - 104.070000 REAL_TIME - 300.000000 START_TIME - 02/03/2021 16:08:09 You¡¯re almost optimized except for the darn x-ray tube cut off at 15kV Dud ? From:
[email protected] [mailto:[email protected]] On
Behalf Of GEOelectronics@... ? " While Sulfur is at 2. so is Mo La1,2.and in that you have a lot of Mo I¡¯d have to call this Mo La1,2." ?
Will check that tomorrow against a Mo only stamp with same setup.
" counts are closer together yet it still has a 65% dead time" ? How are you getting 65%> There is zero deadtime showing on the readout, right?
Can you point out the spikes on the peak you mentioned?
The 27kV was set by adjustment, as was the current. By that I mean they were adjusted while running, then the setting decided, and only then the real test run was started. Don't forget, there is no energy in the beam to speak of anywhere below 20 or so kV. The internal filter knocks that way back. Only the vestigial tungsten L Lines, and those are greatly attenuated. I posted? a test series only a few days ago with that data.
Geo |
