When arriving to the beamline check: previous users still there?, new ones already arrived?, ring current is not 0?, SEC setup is running? Act accordingly, description of all cases is out of scope of this basic refresher. If some (or all) of following items are unclear for you, please undergo asap a real BioSAXS LC training!

Softwares which have to run

  • spec(oh) and spec(exp)
  • iddapli and vacuum appli
  • camera server (pilatus) and SC software
  • BsxCuBE (will normaly start also COServer)

Supposing that the beamline is free of users and some current is in the ring (>1mA), go through the following list (not exhaustive):

  • look to logbook for eventual overnight bugs, problems, suggestions, etc.
  • SC: check levels of rincing water and detergent containers - refill (and prepare new solution in white cannisters) if necessary, empty waste bin into the big 20L one (if full bring it, with help of a troley, to liquid waste deposit near BM05 outside ring and call safety to have a new one, same apply for yellow bin sacs);
  • put a tube with water in well 2-D-11;
  • if SEC set-up running (i.e. pump, UV diode, chiller) and your users didn't manifest interest in using it: put system in water if not done, stop pump, put chiller (off) towards fast shutter location upstream of experimental hutch; note that all these actions are warmely welcome to be done by users or/and LC from previous experiment, however...
  • experience a quick cleaning/unmessing activity in sample prep room;
  • find BsxCuBE window on nela and check potential error messages, log into BsxCuBE with user_of_the_day account (restart BsxCuBE at this occassion is a good initiative) and create subdirectory calibration;
  • take a test image (eventually opening of Front End is necessary, puting Automatic Mode in idappli can avoid this in a near future) and check parasitic scattering from slits (star-like strikes) and/or dirty capillary (homogeneous ring around beamstop), beamstop position and re-adjust if needed using Beamline bricks to move them, check beamstop diode reading (should be in order of 5 x 10-4 at 200mA);
  • by default we use 10x1 second frames at 200mA mode, 10*2(5) secondes at 16(4) bunches and 10 seconds of extra flow time;
  • record water, empty capillary data with Water.xml script: check 2D images and shape of 1D curves for eventual bad mask, crazy/hot pixels, instabilities between frames, SC is cleaning/filling well?, beam mark (red rectangle on robot display) is on right place?, i.e. no meniscus in the beam?, etc.
  • check water I0: should be around 20.3 at 20deg.C, note: if ISPyB/EDNA is not giving directly this, don't panic there are not particles in your water (uff ;-), check it manualy with primus or in ISPyB by looking to primary data proc. using linear scale (took the value at q=1nm-1);
  • modify normalisation coeficient if needed (.xml to re-calculate it is on wbm29control PC desktop and expert psw in BsxCuBE);
  • it is now a good moment to write in logbook: proposal name, your (LC) name, 'dbs' beamstop diode count per second (note ring current), I0 of water measured (at which temperature) and modifications of normalisation coefiecient if any;
  • at this moment users will probably be with you, profit to ask them willing temperatures of storage and exposure unit as cooling (particularly of SEU) can be quite long (~1h from 20 to 4deg.C);
  • ask users to prepare themselves BSA (powder and buffer in the lab fridge), recipe is on the wall of sample prep room;
  • users put BSA (concentration measured by nanodrop) and its buffer into wells 2-A-10 and 2-A-9 respectively;
  • users measure bsa with BSA.xml, note Rg and I0 obtained in logbook and investigate why if not around 3 nm and 66 kDa respectively;
  • check wheather ISPyB with user account shows what it should, note that a SC run appears there immediatelly as started, a HPLC run once finished its data processing and Macromolecules column is filled with HPLC_M only if a peak is found;