• Main INDEX
  • Monthly INDEX
  • PREV
  • NEXT

    User name johna

    Log entry time 03:22:40 on November 7,2001

    Entry number 76197

    keyword=Moeller quad has been off since the shutdown yesterday.

    MCC called to say that the moeller quad was turned off during the shutdown, and not noticed when we restored beam. This is (at least part of) the reason they had to do some significant resteering of the beam to get it back on target. They can turn on the quad and resteer the beam if we want, but they estimate this will take 30-45 minutes (and will require the other halls be shut down for some of that time). Yesterday, BPM H04A was at about -0.2 mm, and BPM H04B was basically zero (so the incoming horizontal beam angle was about 0.2mm/6m = 0.03mr from nominal). Now, the horizontal beam angle is about 0.4mm/6m=0.06mr and the vertical angle is about 0.9mm/6m=0.15mr (these numbers are from the F- magnet screen grab, we have no beam now while they recover from a magnet trip). For now, we will continue to run with these conditions. If we cannot live with the existing offsets at H04A, then we will have to ask them to turn the moeller quads back on.

    Never mind, we will do it now. They are having problems restoring the magnet that tripped off (see previous entry), so I've asked them to turn on the moeller quad now.