Production Run Plan GMp Dedicated Time L-HRS and R-HRS

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Proton Elastic Kinematics

* If you need to increase the spectrometer momentum setting, make sure you cycle Q2 and Q3 as per the cycling procedure.
* Elastic electron rates assume 60 μA on 15 cm LH2 target, 5 mSr acceptance.
* Use the following prescale factors: ps1=1, ps2=1, ps3=1, ps8=100. All other triggers should have zero prescale factor.
* For the optics pointing run, decrease the spectrometer momentum for the left and right spectrometers to 0.85 GeV/c.  The right dipole will need about 2-3 hours to settle.
* Take a one hour run on the optics target.
* After the optics run is completed, then increase the spectrometer momentum back to the elastic setting.  Again, the right dipole will need about 2-3 hours to settle
Make sure to cycle the right Q2 and Q3 when increasing the momentum.
* The 15 cm dummy runs need to be taken at the elastic setting. So keep the momentum as is for this run. * We should take dummy target data to accumulate at least 10% of the LH2 statistics. * A GMp expert will check the data quality.


  • Left-HRS Kinematics: 4th Pass (Ebeam = 8.8 GeV)
    Time estimate: 4 days @ 60 μA
Target Raster Ebeam [GeV] P0 [GeV/c] θe [deg] Q2 [GeV2] Electron Rate [Hz] at 60 μA PAC days at 60 μA Real Time at 60 μA
15 cm LH2 2 x 2 mm2 8.841 2.503 43.0 11.89 0.11 4 (for 38k events) N/A
Optics Off 8.841 0.85 43.0 4.04 31 N/A 0.5 hour (for 55k events)
15 cm Dummy 2 x 2 mm2 8.841 2.503 43.0 11.89 ---- N/A at least 1 hour



  • Right-HRS Kinematics: 4th Pass (Ebeam = 8.8 GeV)
    Time estimate: 4 days @ 60 μA
Target Raster Ebeam [GeV] P0 [GeV/c] θe [deg] Q2 [GeV2] Electron Rate [Hz] at 60 μA PAC days at 60 μA Real Time at 60 μA
15 cm LH2 2 x 2 mm2 8.841 2.101 48.75 12.65 0.054 4 (for 18k events) N/A
Optics Off 8.841 0.85 48.75 5.12 14.7 N/A 0.5 hour (for 26k events)
15 cm Dummy 2 x 2 mm2 8.841 2.101 48.75 12.65 ---- N/A at least 1 hour