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 If a piece of information is incorrect, a link outdated, or the presentation choppy or unclear, the user can just click "Edit Page" at the bottom and then fix the mistake.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: Supplements exposed
Good info thanks. The Det. Temp and Det.HV are shown real time on the bottom right hand corner of the DPPMCA program- good idea to moniotor those for stability or changes. Should be stable over many
By
GEOelectronics@...
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#1493
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Re: Supplements exposed
GeoThis is from Amptek troubleshooting guide?
If the resolution is worse than you expect, then ...Check for good coolingIn Amptek¡¯s thermoelectrically cooled detectors, the back of the detector is
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taray singh <sukhjez@...>
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#1492
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Re: Supplements exposed
" Tip for calibration
It can be difficult to find 2 peaks at extreme end within a specimen or combination.
Sometimes with this method it is difficult to identify peaks
Easier way is use 2 different
By
GEOelectronics@...
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#1491
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Re: Supplements exposed
Here is pic of selenium sulphide(dried centrifugal sample of selenium sulphide suspension / Selsun) using 2048 with threshold correction.
The selenium peaks are seen clearly? and not hidden like the
By
taray singh <sukhjez@...>
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#1490
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Re: Si pin xrf ..1st go
Geo,
These ¡°peaks¡± look to be counting noise. The difference between Kb1 and Kb2 is just 0.013 while the peak difference is 0.08 keV
Dud
Sent: Saturday, October 24, 2020 6:15 AM
To:
By
Dude
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#1489
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Re: Trinitite
There is quite a big mass difference between a piece of DU and the little amount Pu decay in the Trinitite. There can also be a big difference in detector efficiencies.
Dud
Sent: Friday, October 23,
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Dude
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#1488
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Re: Si pin xrf ..1st go
Again no problem. Lowering your max energy to 62 like I do will give more precisi8on per channel. Nothing above 60 will register normally anyway.
Just keep it high enough to see 59.5 for calibration
By
GEOelectronics@...
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#1487
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Re: Si pin xrf ..1st go
Made a Math mistakeIt¡¯s 0.04 not 4At least now I know the relevance of this channel settings?I was taken off guard?I actually did a SF threshold check after calibration?But ?din register when I
By
taray singh <sukhjez@...>
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#1486
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Re: Si pin xrf ..1st go
Taray,
With the 2048 conversion gain your max energy is 88.76 keV so one channel is 88.76/2048 = 0.043 keV/channel. See if one right or left arrow click will give you a 0.04 energy difference.
Dud
By
Dude
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#1485
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Re: Si pin xrf ..1st go
Very interesting set up thanks for sharing.
You need to get rid of the low energy noise as your dead time is 100% with over 10 million noise counts. Run the fast and slow thresholds ad check your
By
Dude
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#1484
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Re: Si pin xrf ..1st go
Taray,
Set cursor somewhere in middle of scan.
Move 1 click left, then 1 click right of original spot. Record keV readings.
Temporarily click off CAL (ICON #18) , repeat test. Record channel #'s
By
GEOelectronics@...
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#1483
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Re: Si pin xrf ..1st go
Taray- show me in pictures offlist or onlist OK?Geo
By
GEOelectronics@...
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#1482
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Re: Si pin xrf ..1st go
Charles,
In the chart below, ignore the intensity%- it has no meaning in this context, but the X-Ray transition energies do.
.
Check out the different K lines on the chart, what you are seeing as
By
GEOelectronics@...
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#1481
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Re: Si pin xrf ..1st go
Anyone knows how to control the energy cursor.Each I move the rt left pc keyboard,it moves by 4 units,Abit too much ?for peaks.Centroid ?method?is ?an?alternative but not?so easyTaray
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taray singh <sukhjez@...>
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#1480
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Re: Si pin xrf ..1st go
CharlesJust noticed thatNee?fast?threshold was 16Did not save it b4 posting?
Taray
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taray singh <sukhjez@...>
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#1479
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Re: Si pin xrf ..1st go
Using a convex mount for your buttons is very interesting. I may have to
try that.
Is your input rate always so high? Mine is typically in the 10 to 20
range. Have you done the Tune Slow/Fast
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Charles David Young
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#1478
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Re: Si pin xrf ..1st go
Taray,
Thanks for the post.? I am in the process of coming up with a similar Am241 device.? It is great that you found that Nickel line with your meteorite, that is useful information also.
Mike
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Mike L.
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#1477
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Re: Si pin xrf ..1st go
Dud
remarkably efficient source / geometry set up...
I am not sure but maybe this is why.?I am using a slightly convex ludlum collimator lead disc
? 9 Am241 exciter are glued on? the outer edge?
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taray singh <sukhjez@...>
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#1476
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Re: Trinitite
Many Pu isotopes lead to uranium, but if one of the precursors is half-life in the millions of years, there won't be very many atoms of U being made now from those in our sample from 1945. If
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GEOelectronics@...
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#1475
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Re: Trinitite
Of course I agree. But given the very accurate ICP-mass spectrometer analysis of this material made by national labs, not by a youtuber, what known isotopes would cause these particular 3 X-Ray
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GEOelectronics@...
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#1474
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