Shay, Can we assume you are working with a reflection mode instrument?
You have two primary sources of background - the primary beam hitting the detector directly, and x-rays scattering from the air rather than the sample. The first of these you control with the divergence slits, but really shouldn't be a problem until you go below 4-5 degrees. If you do scan from those sorts of angles, set the divergence slits to ~0.1 degrees to keep the beam on the sample. I haven't tested it myself, but you could also try reducing the detection window on the LynxEye if you want to go to really low angles (<2 degrees). The air scatter can be reduced with a special screen/knife that you should have received with the instrument, and correctly aligned it will reduce a lot of the background increase you see below 10-15 degrees 2-theta. There should be some instructions in the instrument manual about this. Using a smaller divergence slit (and a receiving slit if you have the option) will also reduce the background from airscatter. I don't think that lowering the tube power will help very much, jools ________________________________ From: rietveld_l-requ...@ill.fr [rietveld_l-requ...@ill.fr] on behalf of Shay Tirosh [stiro...@gmail.com] Sent: 06 March 2016 10:51 To: rietveld_l@ill.fr Subject: Aking for Advice - reduce the current to X-ray tube to avoid director saturation at low angels Dear Rietvelders I would like to avoid director saturation (we have a LYNXEYE detector) when I work at low angles (lower then 10deg). I thought it would be good to lower the current tube to reduce the current. say to 35mA instead of 40mA. Can you please comment on problems it should encounter? Can I correct problems by slowing down my scanning time? Thank you from advance Shay -- _________________________________________________ Dr. Shay Tirosh Institute for Nanotechnology & Advanced Materials Bar Ilan University Ramat Gan, 52900 Israel Phone: +972-(0)30-531-7320 Mobile: +972-(0)54-8834533 Email: stiro...@gmail.com<mailto:stiro...@gmail.com> _________________________________________________
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