User name Volmer
Log entry time 18:33:10 on November 4,1997
Entry number 838
keyword=HMS tracking problem, part 2After redoing the driftmaps for the HMS wirechambers, we looked again at the pattern in the center of Xfp. No final conclusion yet. The fact that this pattern doesn't show up in runs that have been taken before the dc1 u-plane had been repaired, and that the tracking requirement is 5/6 planes, indicates that there is a problem with the u-plane, and with one section (probably card) at that.
The plot below was made to see if there were counts missing (a fact that does not show up in the wiremap). Clearly, the average number of counts stays the same over the whole region (with the exception of the very center) which indicates that events are shoveled from one position to a neighboring one, though the working of that is not clear to me. Could still be a card problem, a wire numbering problem. If it were a rounding error in the tracking code, it probably wouldn't stop this abruptly.
Ideas are welcome!
JV
FIGURE 1
