Settings for fpp_scat_2
Measure the carbon scattering efficiency for Tp = 0.586 for carbon thickness of 22.9 (9''), 30.5 cm (3''+9'' doors), 41.9 cm (1 1/2''+6''+9'').
Beam Energy
4.045 GeV
Beam position
< .25 for x and y for 3A and 3B
Raster size
1.5x1.5mm
Beam Current
» 7-14mA. Set current to give maximum data rate with deadtime < 60%.
Target
15cm LH2
Spectrometer settings
Spectrometer  Momentum  Angle  Collimator 
Electron  3.459 GeV  16.12°  6msr 
Proton  1.202 GeV  53.06°  6msr
 
Magnet settings
Spectrometer  Dipole  Q1  Q2  Q3 
Electron  1.36131 T  2587.94 A  1481.20 A  1369.49 A 
Proton  0.4434 T  898.511 A  514.260 A  475.574 A
 

The electron quads are all set to negative polarity. The hadron Q1 and Q3 are set to positive polarity, but Q2 is set to negative polarity. For a first guess at current for electron dipole either scale from earlier run or use 909 A/T. Suggest that the electron dipole be set to 10-3 level and then quads scaled to match.

Data taking
The T5 prescale should be one. The prescales for T1,T2,T3 and T4 should be set to give less than 5 Hz trigger rate for each. The T8 prescale should be set to maximum.

The trigger setup should be proton_1170-1700.settings .

For each carbon thickness run for 15 minutes. Have allowed 15 minutes for carbon door changes.