Momentum scan for BigBite Commision

Goal - The momentum scan in coinc with HRS produces over-defined protons of known momentum and angles set for the calibration

but shines only a limited part of the BB acceptance. We will therefor mix singles H(e,p) events in to the trigger.

1. Set beam at 1201 MeV (1^st pass), 5-10 microAmp.

   Make sure the singles rate at all BB scintillators are well below

   1 Mhz each.

2. Set HRS(L) at A1 kinematics.

3. Establish a mix of coincidence trigger [HRS(L) (electron) * BB(proton) ] and singles BB (proton).

4. Get data for A1,A2,A3,A6,(G2) kinematics, for both H and C(normal) targets

5. Change energy from 1^st pass th 2^nd pass and get data for A4,A5,(C1,G1) kinematics.

6. Make sure all elements are working. Take enough beam to have ~10,000 per element, for off line analysis.

Analysis -

a) Identify electrons in HRS(L), protons in BB, Identify clean (e,e'p) and (e,p) events.

b) Get the expected momentum distribution using all possible methods and adjust fit/calculation parameters.

* Scintillator hit position.

* TOF Aux-E

* TOF target-E

c) Check dP/P for the different methods.

d) Look for the expected angle vs momentum correlation for the proton in BB.