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Phase II
Now moving on to OTHER excitation.

Transferring our new-found technical knowledge to other sources of excitation, basically starting all over from the previous TUBE tests.

First up-
AmX1?
Amptek Si-PIN 25mm^2 NO Collimator, but a Kapton safety cap.
Source pointed straight up, sensor is at 90 degrees to the source beam.
Sample intersects the beam at 45 degrees.

Pretty much a standard setup, to establish a baseline.
Geo

And here's the finished 30 minute run of the 45 degree angle sample run. With no beam shaping or collimators we were getting 92% deadtime.

Now we re-adjusted the angle for TXRF, this may take a while to get it working, if indeed it does work.

EDIT It does work.?The good and the bad both. Both .mca's attached, one (now correctly labeled) is the 45?degree?target and the other one is the full TXRF mode. The latter shows significant reduction in 59.5 and Np X-Ray interference, but a boatload of? XRF for the added Pb shield. This we can deal with. The main thing is the reduction of actual exciter interference and still enough signal from the sample that can be increased with various means.

Now the real work begins, testing those "various means".



Geo

12 hours in to the TXRF run:

Pb still present of course, we will attend to that and other details subsequently.

Ag- Well formed Ka and Kb peaks.

Interference from exciter- detectable but nil- not a problem with this Total Reflectance (of exciter beam) XRF.

Geo

Enough work, ;let's play a game. The periodic table of elements game.
Bi-

First we do Bismuth. So mark Bi on a piece of paper, then load this file into your DPPMCA program, it should show up on your spectrum chart as live_data_1


This .mca was made with the setup in the picture, run for 2 minutes.

The next post will explain the next step. Prepare to be amazed.

Geo

Bi-N

Now add nitrogen (N) to you paper.

Then load the .mca file live_data_2 into your program.

It was made by removing the sample from the jig and running with no sample target for 2 minutes. This is leakthrough from the exciter and will be addressed in days to come.





Next steps in the following 2 posts, we're almost there.

Geo

This is the germanium step.
Add Ge to your paper= Bi-N-Ge

Then go to the DPPMCA program's menu bar, press ANALYSIS

From the drop down menu, select EXPRESSION, then on the action box add this formula to the EXPRESSION box at the very bottom:

live_data_1-live_data_2

Cut and past if you must- it has to be exactly entered.

Geo

If everything transferred and was entered correctly, these is the last steps and you can add oxygen to your paper.

Push OK on the EXPRESSION menu now.

On your SPECTRA LIST box, HIDE live_data_1 and live_data-2.

On the MENU?bar select DISPLAY and make sure LINEAR is selected.

If everything was transferred and entered correctly there will be a new line on the SPECTRA LIST at the bottom, select that.

The display shown should look very similar to this:


Bi-N-Ge-O Bingo!