Re: [EXTERNAL] Re: [EXT] [External] Re: Step-like basline

2023-09-06 Thread Matthew Rowles
Not only is it a possible explanation, it is the explanation. It represents the tube bremsstralum truncated by the Ni absorption edge. As long as you're careful, removing it shouldn't be an issue, although it is always better to either model it properly, or to not collect such data on the first

Re: [EXT] [External] Re: Step-like basline

2023-09-06 Thread Luca Lutterotti
I am glad you find FPSM an inspiring idea, me and my co-workers will be quite happy if this will results in some citations. The FPSM publication back in 2019 was a troubled submission. It took us more than 3 years as initially was just rejected (for economical reasons, as it would be unfair

Re: Step-like basline

2023-09-06 Thread Luca Lutterotti
It is call graininess, as Miguel said before, these are mosaic single crystals and depending on your source (divergence, spot dimension at different angles etc.) you get each mosaic crystal to create a diffraction peak that especially at low two-theta angle may be displaced a lot from its

Re: Step-like basline

2023-09-06 Thread Le Bail Armel
Dear Frank,Same as you. I have not a complete solution.BestArmelenvoyé : 6 septembre 2023 à 16:57de : Frank Girgsdies à : Le Bail Armel Cc: Rietveld_L objet : Re: Step-like baslineDear Armel,Thanks for this nice quiz!However, after identifying the following spectral impurities: Cu K_beta, W

Re: Step-like basline

2023-09-06 Thread Frank Girgsdies
Dear Armel, Thanks for this nice quiz! However, after identifying the following spectral impurities: Cu K_beta, W L_alpha1,2 W L_beta1,2,3,4 and W L_gamma1, I am stuck now, leaving bout 1/2 to 1/3 of the tiny extra peaks unexplained. Some of them look suspiciously like Cu K_alpha1+2

Re: HiCANS (Hight Current Accelerator-driven Neutron Source)

2023-09-06 Thread Yaroslav Filinchuk
Hi Alan, Accelerator-driven neutron sources are a lot cheaper than spallation sources. Moreover, Figure 54 in the ICONE document shows that the scientific productivity of neutron sources does not depend on the flux of the source. And the biggest point might be the return to building new

Re: HiCANS (Hight Current Accelerator-driven Neutron Source)

2023-09-06 Thread Alan W Hewat
Glad you are following neutron developments Armel. This document points out how French science has suffered due to the shutdown of the only national neutron sources, in Grenoble and Paris. It argues that ESS when it is finally operational, cannot possibly satisfy the national requirement if ILL is

HiCANS (Hight Current Accelerator-driven Neutron Source)

2023-09-06 Thread Le Bail Armel
Interesting document about neutrons in French, though the word "Rietveld"appears only once, page 162, the word "poudre" (=powder) is more frequent :https://2fdn.cnrs.fr/wp-content/uploads/2023/09/ICONE-digital.pdf ++ Please do NOT

Re: [EXTERNAL] Re: Step-like basline

2023-09-06 Thread Alan W Hewat
You are right Radovan. The sample mail-in system is one way of improving SR and N access times. "Discretionary time" reserved for people who have a hot experiment and can come at short notice, is another, together with speeding up the usual proposal system. These mechanisms already apply at ILL,

RE: [EXTERNAL] Re: Step-like basline

2023-09-06 Thread Radovan Cerny
No, you are not provocative Alan. You are right. I have reacted only to the X-ray discussion (no neutrons in the labs). It is a pity that the procedure for getting the beamtime at the synchrotron and neutron sources is still so time-consuming. At least at the synchrotron, there is an activity

Re: Step-like basline

2023-09-06 Thread miguel gregorkiewitz
Nice example for real world, Armel! These huge flakes are by no means single crystals, so I tend to interpret the small peaks in the feet of the maxima as stemming from slightly misaligned regions, sort of graininess. Did you try under the polarizing microscope? Best Miguel El mié, 6 sep.

Re: Step-like basline

2023-09-06 Thread Alan W Hewat
"*The biggest improvement was synchrotron radiation*". No. The biggest improvement for the profile refinement of atomic and magnetic structures (Rietveld refinement in the strict sense) was high resolution neutron powder diffractometers with large area detectors :-) Even SR gives undue weight to

Re: Step-like basline

2023-09-06 Thread Le Bail Armel
Hi,In the same subject.A special "powder pattern" to play with (try to explain all peaks) :http://cristal.org/muscovite.pdfBestArmel ++ Please do NOT attach files to the whole list Send commands to eg: HELP as the subject with no body

Re: [EXTERNAL] Re: [EXT] [External] Re: Step-like basline

2023-09-06 Thread Shay Tirosh
Dear Reitvelders I am overwhelmed with your insightful responses. I am grateful for that. Indeed I have Ni filter and the adsorption added is indeed a good possible explanation since we get similar step-like profiles with completely different materials and samples. With the understanding that

Re: [EXTERNAL] Re: [EXT] [External] Re: Step-like basline

2023-09-06 Thread Reinhard Kleeberg
Dear Radovan, may be you are right, but this great development will unfortunately not help the big number of lab diffractionists to puzzle the patterns to be analyzed in their daily business ;-) Best regards Reinhard Zitat von Radovan Cerny : Dear Reinhard, I wouldn't say "solely from