User name R. Michaels
Log entry time 22:12:03 on November21,2005
Entry number 160934
keyword=Pb tests, part 2Alignment check. Going to dP = -2 % = 1.0775 GeV. Run 3130.
Based on this we decide that the good momentum setting is
same for both arms: P0 = 1.1005 GeV.
Fig 1 == detectors. It shows that: (i) ADC amplitudes still not
very high inspite of 2000V. (ii) Data seems to be mostly in
L-det2 and R-det1 in spectr-DAQ language.
Fig 2 = Alignment criteria. This histogram is filled with cuts:
1. For L-arm, require det2 > 500 and det1 < 550 (i.e. electron
is in det2).
2. For R-arm, require det1 > 500 and det2 < 510 (i.e. electron
is in det1).
Here I use a dirty trick: Since there exist pileups (ntrk > 1)
I still get a peak at the nominal P0 (easily verified by removing
the cuts). So both peaks are conveniently shown, which illustrates
the required alignment change of +23 MeV for both HRS, confirming
the above-mentioned conclusions.
FIGURE 1
FIGURE 2
