Parasitic Production Run Plan R-HRS 48.75 degrees

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Revision as of 16:10, 29 October 2016 by Vasulk (Talk | contribs) (Proton Elastic Kinematics)

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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 15 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 to 0.85 GeV/c.  The right dipole will need about 1.5 hours to settle.
* Take one hour on the optics target.
* After the optics run is completed, then increase the spectrometer momentum back to the elastic setting.  
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. * A GMp expert will check the data quality.


  • 4th Pass (Ebeam = 8.5 GeV) Time estimate: 19 days @ 15 μA
Target Raster Ebeam [GeV] P0 [GeV/c] θe [deg] Q2 [GeV2] Electron Rate [Hz] at 15 μA PAC days at 15 μA
15 cm LH2 2 x 2 mm2 8.517 1.815 53.25 12.54 0.018 19 (for 29k events)
15 cm Dummy 2 x 2 mm2 8.517 1.815 53.25 12.54 ---- 1 hour
Single Carbon Off 8.517 0.85 53.25 5.81 0.83 1 hour (for 3k events)


  • 5th Pass (Ebeam = 10.6 GeV) Time estimate: 22 days @ 15 μA
Target Raster Ebeam [GeV] P0 [GeV/c] θe [deg] Q2 [GeV2] Electron Rate [Hz] at 15 μA PAC days at 15 μA
15 cm LH2 2 x 2 mm2 10.617 1.896 53.25 16.33 0.003 22 (for 5.7k events)
15 cm Dummy 2 x 2 mm2 10.617 1.896 53.25 16.33 ---- 1 hour
Single Carbon Off 10.617 0.85 53.25 6.15 6.0 1 hour (for 21k events)