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User name weinstein
Log entry time 12:46:01 on November 4,2001
Entry number 75795
keyword=target pointing
I have looked at the y_tg spectra for e and h arms for kinematics c+ (64 degrees) and g+ (75 degrees). You can see them at
www.physics.odu.edu/~weinstei/target_cplus_gplus.ps
The top plot shows the electron arm y_tg for runs 1331 (G+) and 1505 (C+). The C+ run has more counts. Note that there is no shift in target position at the level of 0.25 mm (it is 1 bin per 0.5 mm).
The bottom plot shows the hadron y_tg spectrum. Note a) that the central foil has shifted 3 mm, indicating a 3 mm mispointing and b) that the overall spectrum has gotten wider (from 45 to 48.5 mm), exactly consistent with the angle change (since 45/48.5 = sin 64 / sin 75 = 0.93).
Is there some way to doublecheck this 3 mm mispointing with the LVDTs? It would be very nice to have independent conformation of this very large change.