Main INDEX
Monthly INDEX
PREV
NEXT
User name vasulk
Log entry time 07:51:01 on May13,2002
Entry number 3356
keyword=Setting R-arm momentum
After the R-arm polarity change from positive to negative, we cycled Q2 and Q3, and then we set the momentum to 1.177 GeV/c. Q2,Q3 and the dipole automatically started to set to the correct momentum, but Q1 did not. We attempted to reset the magnet a few times, but the current continued to read zero. In the end, we had to manually set Q1 to the correct momentum by setting the current by hand. From what I have been told, to set the momentum all one needs to do is set the desired momentum and all the magnets will set.
We also found that the R-arm dipole took a long time to set to the set point. I know that it typically takes a long time, but the magnet took almost 3 hours to reach the set point. In fact the set current was reached, but for the next hour or so the NMR slowly continued to increase to the set momentum. To reach the desired momentum we had to tweak the current a little, less than 0.5 A.