Very good Charles. I have learned new things too thanks to Dudley. The "Ll" line is not in my X-Ray Data book or XRF charts at all, but the internet served it up, although you would probably never find it unless specifically looking and had a name for it already. Thanks again for that Dud! - Maybe there is an online lookup database on RadPro, NIST or other site?

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Yesterday I spent testing CdTe sensor parameters like Peaking Time and pulse width. This was tedious but productive and the results after many, many tests? is a formula for best low-end resolution, and another one for fastest throughput in the mid energy areas. Both give the clear 5.9 keV Mn line (from Fe-55 source) with the lower noise completely eradicated from view. This alone makes for better scans and the deadtime is reduced to zero because? the count rate is a low figure.

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Beyond the immediate need for basic operator knowledge, I would have had to do this anyway when the brand new?sensor head on the shelf comes into service.

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?After applying the graded shield, then deriving the parameter formulae, a series of tests were done on your Betafite sample, at different channel numbers- 512/1024/2048/4196/8192 could be studied. We will then standardize on one of those.

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Both 1024 and 2048 channels give enough discreet peaks in the 16-17 keV area that 16.61keV Nb Ka peak can easily be picked out from the plethora of Uranium decay series upper daughters' L shell lines. Gotta say though, it really doesn't look promising for positive Nb ID.?

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Likewise XRF with an isotopic source returns too many peaks in that region. That leaves X-Ray tube XRF as the last best. I need to reevaluate those for the Nb lines too, as some may have been misidentified back then.?

Fortunately we already have such scans from the 2013 series using the Silicon-Drift-Detector 1-2-3. -

I won't post the mine or prospect location identification for privacy.

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We can all probably recognize that as originally thought, for heavy REEs and Trans-Lanthanide element identification a? low power microfocus 80 to 90 kVp X-Ray tube with a non interfering target (Cu?) with a CdTe detector would be as good as it gets with today's XRF technologies.

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By the way, shielding is a MUST HAVE.? That little sensor can Gamma Spec a $4 smoke detector, in the original unopened store packaging, at 1 or even 2 feet away. Amazing and unexpected.

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Lots of fun.

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Geo

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----- Original Message -----
From: Charles David Young <charlesdavidyoung@...>
To: [email protected], Mike Loughlin <loughlin3@...>
Sent: Thu, 26 Dec 2019 09:24:36 -0500 (EST)
Subject: [XRF] Bi Ka1/Ka2 bifurcation

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