Privacy and Security Notice

Settings for fpp_pol_1
Beam Energy
1.645 GeV
Beam position
< .25 for x and y for 3A and 3B
Raster size
1.5x1.5mm
Beam Current
6-12mA. Set current to give maximum data rate with deadtime < 60%.
Target
15cm LH2
Spectrometer settings
Spectrometer  Momentum  Angle  Collimator 
Electron  1.219 GeV  36.82°  6msr 
Proton  .9908 GeV  47.49°  6msr
 
Magnet settings
Spectrometer  Dipole  Q1  Q2  Q3 
Electron  0.479646 T  911.840 A  521.888 A  482.527 A 
Proton  0.365674 T  740.965 A  424.089 A  392.104 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.

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_875-1170.settings .

The goal is about 8.6x106 hydrogen elastic events. If a data rate of 1200 Hz is obtained, then this should take 2 hours.