On my web page in zcp.ps under data analysis, I have plotted the z
where the track passes through u=0 for heads of charged tracks.
The first plot is from run 677, mean=5.5". The upper right plot
is for run 1127, delay=6 ns, mean=-31. The lower left plot is for
1092, delay=8 ns, mean=-36. The lower right plot is run 1129, delay=10ns,
mean=-40.
There are many possible causes of the apparent shift, including the
collision point actually moving. It is possible that this apparent shift
is caused by problems in code (my fitting/vertexing code and Ken's tracker
code had to be modified for the new compressed geometry).
If anyone can verify this shift and/or check possible causes, the info
would be much appreciated.
Mary