XRF Wiki
Welcome to the XRF Wiki. This Wiki is a repository of information contributed by members of [email protected]. Members can view and edit the pages. The pages are currently not viewable by the public. The pages below represent a rough overview of the technology and techniques associated with X-Ray Florescence Spectroscopy as well as serving as a place for members to organize the spectra that they have contributed to the forum.?
As a starting point, the pages will be populated by information taken from member posts from the past few years - with references/attribution. Perhaps in time, these pages can be edited by members to make them more complete and less choppy. Members can also edit this page, making the structure of the content more organized.?
Pages can contain information about a particular topic, links to relevant resources (such as manuals, research papers, etc.), links to relevant forum discussions on the topic, book titles, or anything that might be useful.
What follows is very much a work in progress.
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Adding to the Wiki
For those unfamiliar with the Wiki phenomenon, it is basically a user editable encyclopedia. The idea is that there are pages with different articles, which the user can read and also choose to edit if desired. If a piece of information is incorrect, a link outdated, or the presentation choppy or unclear, the user can just click "Edit Page" at the bottom and then fix the mistake. There is also a "Page History," so if you a user were to make a mistake or maliciously destroy a page (which wouldn't happen here) an editor can come along and restore the page to a previous version.?
If you have used MediaWiki (the engine that runs behind the scene of Wikipedia.org) you will be familiar with a certain style of creating an article. There are tags that one uses to change the formatting of the parts of the article. The Wiki on Groups.io uses a different background engine and so the standard MediaWiki syntax does not apply here. Rather, the page is edited using the same tools as one would use to compose a message on the forums. If you are a programmer or someone who likes using the tagged syntax directly, you can access the underlying page source code, be activating the advanced editing toolbar (the icon with three lines on the far right of the basic toolbar) and then clicking on the source code icon <> on the far right of the Advance Editing Toolbar. You will immediately notice that the underlying source code is HTML. Most things can be done just by using the various icons, but advanced features like table can only be implemented by manually writing the source code. (Although there are website available that will generate the source code for you through a graphical interface.)
Here are some useful resources from Groups.io:?
Wiki Guide for Users and Editors
Message Composition Tips and Tricks
Overview of XRF
X-Ray Florescence vs. X-Ray Diffraction
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Hardware
This section describes the hardware used for XRF. We will describe the basic theory of operation of each stage in the processing tool chain and then present different commercial systems that are available as these systems are often integrated together.
[Editor note: General theory needs to be in an independent page separate from specific manufacturer information.
[Editor note - question: Should this be arranged by category, e.g detectors, preamps, etc or by manufacturer with the manufacturers product line on one page. Perhaps it's best to put a list of products with theory but the details of the products on a manufacture page...]
Detectors?- what's available, theory of operation, tradeoffs
Detector Cooling?- keeping detectors cool to avoid thermal noise and keeping the TEC from overheating
Preamps?- theory of operation, brief summary of what out there (and what not to do - such as trying to use a PMT preamp for a SiPIN diode...)
Pulse Processing Theory - high level overview of the stages of going from detector pulse to channel peaks on the computer
Commercial Systems - many commercial systems are integrated so it seems to make sense to present, for example all Amptek products together. [question: are their other affordable integrated systems besides Amptek?]
Amptek XRF System
Activation Sources - what do you use to make the sample fluoresce (that's within the amateur budget and doesn't require special licensing)
Software
- Device Control Software - what do you use to collect the data from the detector system
- XRF Analysis Software - what do you use to analyze the data, especially for quantitative measurements (composition percentages, thin film measurement)
- Free Software Tools
Note: there may be software packages that possess some or all of these characteristics.
Materials Spectra
Metals Spectra
Historic/Archeological Spectra
Reference Materials Spectra
Household Objects Spectra
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Resources
Videos
Articles
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Non-XRF Techniques
Gamma Spectroscopy
Raman Spectroscopy
FTIR - Fourier Transform Infrared Spectroscopy
Atomic Emission Spectroscopy
Inductively Coupled Atomic Emission Spectroscopy
Spark Emission Spectroscopy
Atomic Absorption Spectroscopy
LIBS - Laser Induced Breakdown Spectroscopy
Photoacoustic Spectroscopy
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Re: Trinitite
Suppose your Pu is Pu-243 you¡¯ll get an Am decay x-ray Pu-239 a U x-ray. If its Np-234 you get a U decay x-ray, if its Np-237 it¡¯s a Pa x-ray. For Pa-234 you get a U x-ray if its Pa231 you get an
By
Dude
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#1473
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Re: Trinitite
" A Pu decay U x-ray looks like a Pa U decay x-ray or any other U x-ray"
I mentioned Pa-234m decay to U-234 before. Pa-234m decay can be eliminated by the lack of other peaks at the appropriate
By
GEOelectronics@...
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#1472
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Re: Trinitite
That was not missed by them even though it¡¯s a wet chem. Pu extraction aliquot, but you cannot assign these x-rays to any particular source. So its labeled a U x-ray not Pu. A Pu decay U x-ray
By
Dude
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#1471
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Re: Trinitite
An interesting chart from a study by Los Alamos National Lab concerning precision mass spectrum analysis of Trinitite. It shows there is an across the board 3 orders of magnitude more Pu-239 atoms per
By
GEOelectronics@...
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#1470
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The Crayola challenge
It has been rumored that Crayola (of crayons fame) has a new brilliant blue
crayon called bluetiful. What is its elemental composition is the question.
The first to submit an MCA file documenting
By
Dude
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#1469
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Re: Si pin xrf ..1st go
Taray,
Looks good with the 2048. There are two things that could be done for your setup. The first is the count time, you really need much more count time to resolve things especially close lines and
By
Dude
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#1468
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Re: Supplements exposed
Charles?
I plan to do that next
Can just let it run by itself for hours
Have seen it working?
But not keen in this case
The composition of these supplements may be altered by
By
taray singh <sukhjez@...>
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#1467
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Re: Supplements exposed
Taray,
So why don't you let this run for a long time so you can get some decent
counts? Se is almost certainly there but to identify the other peaks with
certainty you will need more than 1024
By
Charles David Young
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#1466
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Re: Si pin xrf ..1st go
OK, your Np L X-Rays are spot on, so good job.You are getting no 59.5 backscatter?Geo
By
GEOelectronics@...
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#1465
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Re: Si pin xrf ..1st go
GeoYes?Used centroidIt was quite a struggle?The software has a bad habit of rejecting?Taray
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taray singh <sukhjez@...>
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#1464
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Re: Si pin xrf ..1st go
Hi Taray, did you re calibrate after changing to 2048 channels?
I'll be glad to walk you through it if needed.
Geo
To: [email protected]
Sent: Friday, October 23, 2020 8:35:07 AM
Subject: Re:
By
GEOelectronics@...
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#1463
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Re: Supplements exposed
Charles
I repeated the scan with some tabs in a plastic
The spectrum is quite alike
Did a 2046 channel with gain upgrade
Not a long spectrum..
I am primarily interested in scanning some supplements as
By
taray singh <sukhjez@...>
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#1462
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Re: Si-PIN Detector PEAKING-TIME-TEST
Conclusions-
Based on the short tests of each available peaking time settings, in the first post of this topic:
4.8us (what we've been using until now), is adequate and could be retained for general
By
GEOelectronics@...
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#1461
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Edited
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Re: Si pin xrf ..1st go
Dud
I upgraded to 2048 with higher gain .
I repeated the x ray apron
It? is? Pb/Sn like you? said
Pb /Bi? lines are tricky and adjacent on the periodic table
Taray
By
taray singh <sukhjez@...>
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#1460
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Re: Si-PIN Detector PEAKING-TIME-TEST
ATTACHED:
,mca for 19.2us Peaking time with same settings as 4.8us PT
.mca for 19.2us Peaking time with new auto tune fast-slow routine run
To auto tube the source must be removed, which is all part
By
GEOelectronics@...
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#1459
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Re: Si-PIN Detector PEAKING-TIME-TEST
Geo / Charles,
Changing only the peaking time is not going to give you a good idea of what an optimal setting should be. These things interact with each other and need to be set together, The noise
By
Dude
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#1458
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Re: Si-PIN Detector PEAKING-TIME-TEST
Run it for the same time change only one variable at a time
Dud
Sent: Thursday, October 22, 2020 8:52 AM
To: [email protected]
Subject: Re: [XRF] Si-PIN Detector PEAKING-TIME-TEST
This next scan
By
Dude
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#1457
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Re: Si-PIN Detector PEAKING-TIME-TEST
No not auto resetting LLD etc. I believe you must remove the source to do that. I'll include that on the way back down from 25.6 us which to my eye is the sweet spot.
This series is looking at gross
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GEOelectronics@...
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#1456
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Re: Si-PIN Detector PEAKING-TIME-TEST
Geo,
Did you auto reset the fast and slow thresholds for the 9.6 usec count? Note the input count well exceeds your total count meaning there is still a lot of low energy noise that needs to be taken
By
Dude
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#1455
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Re: Si-PIN Detector PEAKING-TIME-TEST
I don't know why Charles. That's more a question to be answered by a digital expert.
George Dowell
Geo
To: "XRF" <[email protected]>
Sent: Thursday, October 22, 2020 10:56:10 AM
Subject: Re:
By
GEOelectronics@...
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#1454
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