by Arun Saha
Last updated on 01/20/99
This note is to remind users the steps to follow everytime beam is delivered into Hall A after a major shutdown or after a major retune. The attached memo to the MCC operational crew is to remind THEM of the procedure THEY must follow in delivering beam to the hall. It is the responsibility of the Hall A experimental crew that the quality of the beam being delivered is acceptable. If necessary, do a harp scan of Harp #6 (right after the last BPM) after good cw beam has been established to the hall, both with and without the raster on. This note is to make sure that beam delivery to Hall A is done according to the prescribed operational procedure. Everytime beam is delivered into the hall after a major shutdown or after a retune, it is very important that these checks in the operational procedure be performed. This is to prevent immediate and catastrophic damage to sensitive equipment along the beamline and the target systems in the hall. 1. With pulsed beam, make sure the relative orbit in Hall A is zero. Are BPM relative positions zero and well calbrated (esprecially the last two BPMs (IPM1H03A and IPM1H03B) just before the Hall A target. There should be no doubt that the beam positions read out from the last two BPMs are correct. 2. Make sure the 5 ION Chambers along the Hall A line are working and the readback on the medm screens are playing back the correct values (i.e. they are not frozen). This is essential, as the experimenters have no other way of knowing whether the radiation levels in the hall are being recorded properly or not. If the ion chamber readbacks are not functioning, software on call needs to be informed immediately to get it fixed. NONE of the 5 ion chambers should ever be masked during beam delivery to the hall except with my permission. (or Kees DeJager) 3. Make an aperture scan of the beam through the Hall A fast raster ceramic pipe. Center beam in aperature using ion chambers as feedback. E-log the beam aperture. 4. BScope data should be taken, studied and recorded before acceptable beam is delivered to the hall. It also needs to be recorded before every shift and whenever the experimenter need it.