Articles by Brian
Dear readers. I felt the old theme, “Redline”, had not seen an update in too long a time. After searching for a while I found this new theme. Let me know if you like it or not; changing back is always an option. The header image still needs to be changed, and I hope that with later posts the post images will be scaled better to the post. If anyone can recommend a better theme, please let me know.
During last week’s visit to BAM in Berlin, I and Ingo played around with some equations. In particular, we were curious if we need to do something special to get the scattering from a sample in a capillary, i.e. a sample between an upstream and a downstream sample cell wall. Long story short: we arrive at a rather ordinary equation after a lengthy derivation.
Dear reader, In a few moments, I will be boarding the flight to Europe for the whirlwind SAXS tour and diamond experiments. I will post during and about the trip, so posts should appear with irregular timing on this site, so check frequently! feel free to stop me for a coffee as well! regular programming will resume in two weeks.
I’ve been working on a lot of things of late, but none are yet in a state to show here yet. However, when talking to a colleague last week, I found it hard to explain why I do what I do: why I am so focused on metrology. But maybe I can explain it a little here (warning: rambling ahead! I have been reading books and may come over as slightly lyrical).
See the previous posts in this series here: Part 1, Part 2 and Part 3 Very recently, Bruker upgraded their SAXS instrument in our building. This is a typical 3-pinhole 2D SAXS system that was largely designed by J. S. Pedersen in Aarhus a decade or so ago. This particular version was at NIMS in the Quantum Beam Unit / Neutron Scattering Group, and was using chromium radiation (a very low energy radiation). Now that its source has been upgraded to my favourite molybdenum type (a high energy radiation), it is time to check all of its corrections once more, starting with the flatfield.
As indicated last week, some spare time has been spent trying to re-derive a correction for separating sample container scattering from the sample itself. Normally, a simple background subtraction suffices, but for those who want to go the extra mile (and in particular for those working with strongly absorbing sample containers and samples), you need something a bit more fancy.