Series of Mott measurements on Jan 11th

mott5.11Jan02_08:45:43 65.54 +/- 3.28stat +/- 0.78
mott5.11Jan02_08:51:17 67.08 +/- 3.20stat +/- 0.80
mott5.11Jan02_09:01:55 73.46 +/- 3.32stat +/- 0.88
mott5.11Jan02_09:19:31 71.67 +/- 2.07stat +/- 0.86
mott5.11Jan02_09:25:21 70.82 +/- 2.07stat +/- 0.85
mott5.11Jan02_09:30:57 74.92 +/- 1.06stat +/- 0.89
mott5.11Jan02_09:36:55 73.70 +/- 1.96stat +/- 0.88
mott5.11Jan02_09:47:15 78.70 +/- 2.04stat +/- 0.94
mott5.11Jan02_09:57:57 70.72 +/- 2.02stat +/- 0.84
mott5.11Jan02_10:08:23 73.47 +/- 2.09stat +/- 0.88

 From Jan 11 elog 1020404

mott5.11Jan02_08:45:43 resetting timer - data no good
08:51:17 half wave plate out, laser phase -8 degrees (where we have been
running), 0.9 uA beam current, attenuator C at 120, open slit:  67%
polarization (5 min run)

09:01:55 half wave plate in, laser phase -8 degrees, 0.9uA beam current,
attenuator C at 120 degrees, open slit: 73.5% polarization (5 min run)
09:19:31 half wave plate out, laser phase -8 degrees, 2 uA beam, Atten at 300,
slit at 60: 72% (5 min run)
09:25:21 half wave plate in , laser phase -8 degrees, 2uA beam, Atten at 300,
slit at 60: 71% polarization (5 min run)
 (9:19 and 9:25 runs at rather high background rates - moved spot on foil a bit
and redoing 9:25 run again)
09:30:57 half wave plate in, laser phase -8 degrees, 2uA beam, atten at 300,
slit at 60: 75% polarization (with better steering onto mott foil)
9:36:55 half wave plate out, laser phase +4 degrees(tail), 0.2 uA beam, atten
at 300, slit 60: 74% polarization (10 minute run)
9:47:15 half wave plate in, laser phase +4 degrees (tail), 0.2 uA, atten 300,
slit 60: 79% polarization (10 minute run, reasonable background values)
9:57:57 half wave plate out, laser phase -18 degrees (head), 0.2uA, atten 300,
slit 60: 71% polarization (10 minute run)
10:08:23 half wave plate in, laser phase -18 degrees (head), 0.2uA, atten 300,
slit 60: 73% polarization (10 minute run)


The weighted average of the Mott measurement ( excluding 65.54, 67.08,
78.70) is 73.3 +- 0.68 . The Wein angle was 71.2 degrees.  The beam energy
was 5755 which is 569.098 GeV/pass, soexpected longitudinal polarization 
in  Hall C is 0.951*73.3= 70.01 +- 0.7 with +/- 2.4 systematic from 
a 5x10-4 uncertainy in the beam energy. With a leakage current of 2%
expect 70.01*.99 = 69.3 +- 0.7 +- 2.4
The average with the Moller is 65.55 .

Asked Joe Grames to give final numbers for these Mott polarization runs.

******************** Parallel target field running ************

Feb 13th changed injector setup so that Hall A could get high 
polarization. Spin angle changed to 60deg

Spot move Feb 14th


From ELOG 1077277 Feb 21th ( Mott measurements on Feb20th)

The table gives the beam polarization at the cathode, ie : measured at the Mott
corrected by the Wien angle (60.4 deg). The Mott measurements were done
yesterday during MD and the results were given in elog 175567. Those numbers
should be easier to use.

  
 
Beam polarization at cathode laser 	Pe (%) +/- stat 	wave-plate
A 	+73.6 +/- 0.9 	in
A 	-73.5+/- 1.4 	out
A 	-73.3 +/- 1.1 	out
A 	+74.1 +/- 1.1 	in
B 	+72.5 +/- 1.1 	in
B 	-72.6 +/- 1.2 	out
C 	+71.8 +/- 1.0 	in
C 	-71.2 +/- 1.0 	out

The average of the Hall C is 71.5 +/- 0.71 . The beam energy
was 5755 which is 569.098 GeV/pass. The Wein angle was 60.2 .
The expected longitudinal polarization in  Hall C is 0.99*71.5=
70.78 +- 0.7 with +/- 1.0 systematic from a 5x10-4 uncertainy
in the beam energy. The average with the Moller is 70.74 .