User name E.Chudakov
Log entry time 18:43:33 on August 1,2006
Entry number 176731
Followups:
keyword=Spin dance results10:00-12:00 Moller commissioning
12:00-18:40 Spin dance
Moller magnets settings:
Q1 GL = 9020 Gs
Q2 GL=0
Q3 GL=0
D Bdl=134000 Gs*cm
The dipole is at lower 18% lower current than initially set in order to remove a huge
Mott peak from the top counters.
The Moller spectrometer was tuned to a range of scattering in CM: 40<θ<80.
No coincidences could get into the acceptance. The single arm asymmetry was about 0.5%,
which is about 5 times lower than the value observed at higher beam energies with
the regular optics. Only relative polarization measurement could be done. We use an average of asymmetries in both arms.
The spin dance results are presented in the attached plot. The optimal Wien angle for
Hall A is 11 ± 0 degrees.
The expected optimal angles are 10 deg for Hall A and 71 deg for Hall C.
FIGURE 1
