The known truther as you put it is Dr. Harrit.
I'm well aware of who he is.
The SEM XEDS spectra you like to misrepresent, was taken from Dr. Harrit's paper WHY THE RED/GRAY CHIPS ARE NOT PRIMER PAINT which he wrote in May 2009.
I do not misrepresent anything as I consistently show.
When you quote the analysis "WHY THE RED/GRAY CHIPS ARE NOT PRIMER PAINT" you will know, as I've shown above, that none of us including anyone here at JREF knew of the existence of Laclede red joist primer paint until Ivan Kminek pointed this out. Harrit's analysis, in the above, does not take into account that fact that there is documented evidence that Laclede red joist paint was used in the towers, so his analysis does not take into account a known primer paint other than Tnemec red. (We all missed it so there is no criticism on this point).
However, it's out of date. We at JREF have been including this fact in our analysis since it was brought to our attention. No subsequent evaluation by Harrit has occurred. Why hasn't Harrit updated his "Why the red/gray chips are not primer paint" in order to take in the new information? In fact this information is now old and well known.
What's more I'll show that the idea of elements being masked by "noise" or incorrectly identified by the EDX detector is not consistent with regard to the identification of elements S, Ca, Cr and Sr in the EDX spectrum as used by Harrit.
Here is the spectrum:
followed by the four different samples in Harrit et al:
Left: Figure 7 in Harrit et al, showing the four different samples investigated. Right: The same spectrum as in frame (a) with intensity (vertical) and horizontal scales expanded. Minute signals in level with the noise are observed from sulfur, calcium,chromium and strontium.
http://www.ae911truth.org/downloads/documents/primer_paint_Niels_Harrit.pdf
The figure above is taken from this page. So we have direct correlation to Fig 7 a). We would also expect this detail to be present in the other figs 7 b), c) and d).
In order to understand what Harrit means by the word noise we have to have an understanding of what this phrase means.
I shall attempt to do this so that everyone can follow because the science behind XEDS/EDS/EDX/EDAX gets highly technical very quickly.
I'm going to give the following for a very quick reference and anyone interested should look at other sources.
http://en.wikipedia.org/wiki/Scanning_electron_microscope
http://en.wikipedia.org/wiki/Energy-dispersive_X-ray_spectroscopy
There is an interaction between the electron beam (of the SEM) and the different chemical elements that make up the material that the beam is focused upon. Remember that an atom is made up of a nucleus containing protons and neutrons and outer shell(s) containing electrons.
I am assuming that Dr Harrit, when he is talking about noise, is talking about the
Bremsstrahlung radiation or continuum/background x-rays.
Electrons from a source do not always interact with an atom consistently. Some electrons will pass through, some will interact, either by being deflected by the shell of electrons surrounding the atom and others will have sufficient energy to remove an electron from from one of the orbitals that the original electron occupies in the atom.
When an electron form the SEM beam is deflected then the following occurs:
http://www.ndt-ed.org/EducationResources/HighSchool/Radiography/bremsstrahlung_popup.htm
The subsequent x-ray produced by this interaction shows up on the EDX spectrum as a "bump" followed by a tail or tailing off with increased (voltage) KeV for a given element.
Here is an addition page that should be understandable:
http://www.ammrf.org.au/myscope/analysis/eds/xraygeneration/bremsstrahlung/
However, we observe spikes or peaks in the EDX spectra so what are these peaks attributable to?
The peaks are due to incoming electrons from the beam knocking out an electron occupying a "space" in a specific shell of the atom. When an electron is knocked out of it's orbital then another electron from a higher orbital "falls" into the the vacancy. In doing so this electron reduces it's energy and the difference in energy is released and emitted as an x-ray.
It's this x-ray that is picked up by the EDX x-ray detector. So, subsequent x-rays that are received by the detector in the SEM-EDX can be analysed. Emitted X-rays will have different energies depending upon the atoms that the original electron beam has interacted with.
Light atoms/elements have fewer layers (shells of electrons) than heavier atoms/elements. Electron layers are called orbitals and these layers or orbitals are have labels with regard to x-ray notation.
Orbital names
Orbitals are given names in the form:
X\,{\mathrm {type}}^{y}\
where X is the energy level corresponding to the principal quantum number n, type is a lower-case letter denoting the shape or subshell of the orbital and it corresponds to the angular quantum number ℓ, and y is the number of electrons in that orbital.
For example, the orbital 1s2 (pronounced "one ess two") has two electrons and is the lowest energy level (n = 1) and has an angular quantum number of ℓ = 0. In X-ray notation, the principal quantum number is given a letter associated with it. For n = 1, 2, 3, 4, 5, …, the letters associated with those numbers are K, L, M, N, O, ... respectively.
http://en.wikipedia.org/wiki/Atomic_orbital
An electron emitted from an electron gun must have sufficient energy to dislodge an electron from an atom's shell.
When we look at the an EDX spectrum then we are looking at x-rays being detected by these two interactions; slowing/braking and deflection (Bremsstrahlung/continuum or background) and electrons being knocked out of a shell and an electron "dropping" into the lower shell producing the subsequent x-ray. Depending on which higher shell the electron "drops" from, then the x-ray associated with that drop has a different wavelength or energy. On the EDX spectrum these x-rays are plotted by their energy. This is why we see multiple peaks for the same element in the spectrum. You will often see EDX spectra with labels K-alpha and K-beta. These correspond to electrons from different higher shells filling the space or void left by the removed electron and are refer to as "transmission lines".
http://www.seallabs.com/how-sem-eds-works.html
http://micron.ucr.edu/public/manuals/EDS-intro.pdf
Tools are available for looking at the different K-alpha and K-beta etc:
http://csrri.iit.edu/periodic-table.html
http://www.unamur.be/services/microscopie/sme-documents/Energy-20table-20for-20EDS-20analysis-1.pdf
In the above EDX spectrum from chip a) we can clearly see that there are a number of elements that have been identified by both their K-alpha and K-beta emissions: Ca, Cr, Fe and Sr.
Sulphur has a K-alpha 2.30 at and a k-beta at 2.46 Kev.
Statistical analysis is performed by the SEM software, which compares background x-rays to x-rays emitted by these transmission lines for each energy or voltage for EDX analysis and therefore determines whether an element is present or not because the detection is based on a count rate and therefore electron beam current.
Harrit's statement
Minute signals in level with the noise are observed from sulfur, calcium, chromium and strontium.
does not mean that those signals are illegitimate.
The signals S, Ca and Cr are not level with the Bremsstrahlung. Anyone with a pair of eyes can see this. Elements S, Ca, Cr show distinctive peaks above the background. Ca and Cr not only show distinctive peaks but those peaks are consistent with the k-alpha and k-beta transmission lines. (S has very close K lines so K-beta isn't labelled). Whilst Sr is observed at the tail end of the spectrum it's notable that both K-alpha and k-beta lines are observed at 14.1 and 15.8 KeV respectively.
There is absolutely no way that anyone can dismiss these elements being present due to noise because the k-alpha and k-beta peaks correspond. I suspect that Miragememories has misinterpreted Harrit's words in order to hand-wave away the fact that these elements were observed as being present in the chip for his own ends.
MM - in order to show that these elements were not present in the above spectrum then you must show what you are basing this on. I expect a technical explanation for the misappropriation for all 4 elements; S, Ca, Cr and Sr.
There is no way that EDX analysis is misreporting 3 elements with both K lines shown as well as S.
You cannot simply say they are part of the noise and therefore dismiss them without adequate explanation, as I have shown.
Then we have the following statements from Jones and Farrer:
6. Jeff notes that in his TEM analyses he observed “very small nanometer-scale) Pb particles in the TEM samples” as well as strontium and chromium in small amounts. (Much of the TEM analysis was performed at higher magnification than used in the SEM analysis done in the paper.) Thus, red/gray chips which match ours will show these same elements under TEM analysis.
http://911blogger.com/news/2012-09-08/letter-regarding-redgray-chip-analyses
So on the one hand we have MM claiming that Sr and Cr are merely symptoms of noise in the EDX spectrum yet Jones and Farrer are confirming that Sr and Cr are indeed present in the chips and to be expected!
So are we to believe that noise is only noise when it doesn't suit your purposes Sunstealer?
Nope. I've explained it above. You are the only one claiming that noise rules out the presence of these elements which goes against what Jones has stated.
Miragememories - Are Cr and Sr signals noise as you state or are Cr and Sr present as stated by Jones?
This is pointing out how you distort and misrepresent the truth in order to convey a false truth.
There is only one person doing that here and that is you. You had to back-peddle on the false claim that resistivity was used as a method for isolating chips of interest and it's taken you over a year to acknowledge that the spectra for the red layer in chips a-d) and shown in Fig 7 is the same material.
You have once again stated something that you cannot back up:
In the laboratory the thermitic red chips and the non-thermitic red chips revealed themselves during DSC testing. MM
Show us where this is stated in the Harrit et al paper.
I know you won't because you can't. It's not there. You continually misrepresent or lie about the paper we are discussing.
Then you laughable say:
It is particularly outrageous because you promote yourself as an in house expert and expect everyone to trust you as such.
I detect your bitterness, but that is not surprising. You cannot refute what I say because you don't have the technical knowledge to do so. I don't expect people to trust me, which is why, wherever possible, I post links backing up my claims. Any one can read what I have written and get conformation.
I've refuted everyone of your complaints as to why you think that Millette has the wrong chips and you've simply ignored most points because you can't refute them. You've then concentrated on the points you think you can win. Those points have been whittled down and consequently shown to be wrong.
Not only that, but you appear to be at odds with Jones and Farrer on the subject of Sr and Cr being present in the chips.
The very fact that LaClede red primer paint has Strontium Chromate as part of it's constituent seems to have been lost on you as well as Jones, Farrer, Harrit etc even though Jones states that the two elements making the compound are expected to be evident.
Why on earth would Sr and Cr, along with the other elements shown, be used in thermite? Give your reasons.
We know why those two elements would be observed in primer paint and those two elements have been observed, as stated by Jones.
Oystein did a huge amount of work showing that the documented composition of Laclede red primer paint would show identical EDX spectra as seen in Harrit et al. The same data applies to Millette. It's all there.
It is, though, their selection method as described in the paper and confirmed later elsewhere.
