Identifying Elements WITHOUT XRF [a DIY project]

We are all hoping that @Neptunium will help us to understand why increasing the proton count in a linear way should result in a straight line on a log-z graph.

Time, distance, shielding brings back memories of sitting in the doghouse joking with the Schlumberger hands about how cute a three head kid could be.

You did a great job on explaining the back-scattering and I love the knowledge you impart. Thank you!

I actually don't think I've ever seen anyone else here do this before, and that's really saying something considering how obsessed I am with exactly these kinds of science videos on the site! (I too have many a time wished to own and simultaneously lamented the insane cost of XRF devices) Thanks for your review and recommendation of the "Little Garden" spectrometer again, I just got mine and the spectral resolution is EXCEPTIONAL, I'm thinking of making it a little better by using a pair of razors for the entrance slit instead of the printed pla. There is another industry tool used to do what you are attempting here which doesn't use XRF or beta backscatter, it's a "spark spectrometer" or "spark optical emission spectrometry". Bruker and some other companies sell high end units to the metals industry for process analysis, but I think you could do a rudimentary version of it with none other than our LG spectrometer itself! It's just a spectral analysis of the plasma light emission from a low voltage spark contacting the metal in question. It's destructive, but only very slightly. I will also echo the comments of others urging the introduction of a 1cm thick piece of plastic before the lead in the shield portion of the device to suppress brems production in the lead (may as well keep the lead to block the few Y90 gammas).

Great video as always. I like the introduction of characters, it's a bit more entertaining. I suspect a few "serious" people will have problems with it. My "Little Garden" Spectrometer is on the way!!

This is a really fun and interesting video! If anything, it's a great demonstration of why the handheld analyzers are so expensive. There's so much that has to be taken into account to properly measure each thing. 😮 Well done!

Success or not, It was an interesting experiment and it was educational as well!

e Exceptional video with clear, crisp narration!

11:00 It actually makes sense that backscattering of beta particles from light elements consists of slower (less energetic) particles; smaller nuclei will have a weaker force acting on the particles meaning faster particles will not be curved as strongly and will not hit the detector. When measuring heavier elements, the opposite is true.

OK, you got me with that penultimate sentence. I'm in.

"Patience is a finite resource around here"😂

Now that was a very good video! I did try something like this with the KC761B but didn't make this nice rig and much less scientific patience... So it didn't bring the results I hoped. Now, I'll try again.

This would be interesting for testing gold (and silver). Pb and Au are a couple of atomic numbers apart, and Pb is commonly injected into gold bars. The usual tests are density (weight and dimensions), a "ping" test to measure speed of sound (also using an ultrasonic thickness gauge), resistance (using eddy currents, a pulsed electromagnet next to it), and destructive testing using acids.

Thank you for sharing this interesting experiment. Especially your measurements of electron backscatter spectra with the Measall KC761 of Al and Pb raise my curiosity. The energy distribution of Al looks very sharp. Did you compare it with direct beta radiation from Sr 90 source? Maybe not so easy, because of the much higher flux. Increasing the distance would help, but which role plays scattering in air? Primary electron energy should be 546 keV, if I am right? But there can be inelastic scattering in the source itself, maybe broadening the source spectrum (?).

It's better to shield beta radiation with plastics, not lead. 5mm plexiglas is a good protection. This avoids the generation of x-ray that will travel farther. Also, always use some glasses, betas are terrible for the eyes. Nice experiment, maybe it could have also been done by measuring the noise in a camera in the dark caused by the back scattering. For an even more low cost way.

Nice, thanks!

Are there any cheap XRF guns you can review?....I did buy a Radiacode 103 because of your video. Thank you!!

Cool viddy! What about this experiment with the radiacode? Peace!

If you measure low energy radiation, put a thick copper plate after the lead, otherwise the lead will cause a shower of lower energy radiation as result of the slowing down of the initial particles you want to shield.

courage experiment, if you could have compared the incident count rate to diverted, the ratio could have been related to element identification. Also the diode detector or even plastic scintillator could make better gamma discrimination that would also increase beta sensitivity. The question is also, how does the diversion angle depend on core mass? If you could measure on two different angular positions, the subtraction may give angular difference. This reminds on bremsstrahlung, that is principle of x-ray, as the high accelerated electrons do divert over the wolfram core and by reduction of speed do emit x-rays, but here the effect is not as significant likely to have E=mc2 resulted x-ray.