Optics Run Plan

By Jin Huang's suggestions, I (Zhihong Ye, 04/08/2011) make a run plan on optics data taking

Run plan with 1 pass beam

a) Vertex Calibration Data: Raster Off, 1 Pass Beam, Elastic Data, 200K events (~2 hours)

    Sieve Out, Delta P0 Scan on Multi-C and Single BeO(or other single foil target): At least three point (-3%,0%,3%), but prefer five points(-4%,-2%,0%,2%,4%).

b) Theta,Phi,Delta P Calibrate Data: Raster Off, 1 Pass Beam, Elastic Data, 200K events (~2 hours)

    Sieve In, Delta P0 Scan on Multi-C and Single BeO(or other single foil target): Five points(-4%,-2%,0%,2%,4%) for better momentum calibration.

c) New Matrix Quality check for regular beam: Raster On, 1 Pass Beam, Elastic Data, 200K events (~ 10 mins)

    Sieve In, Delta P0 = 0%  on Multi-C.

d) New Matrix Quality check for Regualr Kinematics, and correct Vertex scaling effect: Raster On, 3 Pass Beam, 200K events (~ 10 mins for each kinematics)

    Sieve In, Delta P0 = 0%  on Multi-C.

e) Take one arm Optics data while the other arm is changing momentum, so save some beam time.

f) If we want to only take one set of optics data for different angles, we need to have survey results on real angle values.

  If we can not have the angles surveyed, we need to take at least three set of data with three different angles above.

Special Treatment on R-Q3

Since Q3 of R-HRS can only set to about 2.8273GeV/c while we require the center momentum of R-HRS run upto 3.155 GeV/c, we need to do some special treatments,while we are taking Optics data, if we require better resolution of reconstruction.

There are two way:

1, Only one set of Optics Matrix:

   Take the highest momentum we can get on all magnets, for example, D,Q1,Q2 = 3.155GeV/c, Q3 = 2.8273 GeV/c. Then if we need to take optics data with lower 
   momentum, while reducing D,Q1&Q2, scale down Q3 setting witht the same ratio. For  example, if D = 2.79, Q3 = 2.79*2.8273/3.155 = 2.50GeV/c.

2, Fix Q3, each Kinematic setting has its own matrix, which will increase the volume of work on Optics calibration.

Alterate Plan with 3 pass beam

(04/11/2011 Zhihong Ye) If it causes us too much time to change beam to 1 pass, we might consider another plan with 3 pass beam. The price to do this is we will get much lower rate, hence need to take longer time for each optics run. We need to calculate the rate and time, and make a balance plan.

a) Vertex Calibration: 3-pass beam, Take QE data, with dP=0%,  Sieve Out, Raster Off, Single Foil(BeO or heavier).    (Rate and How long?)

b) Multi Vertex Calibration: 3-pass beam,Take QE data, with dP=0%,  Sieve Out, Raster Off, Multi-Foils.    (Rate and How long?)

c) Angle Calibration: 3-pass beam,Take QE data, with dP=0%, Sieve In, Raster Off, Single Foil.    (Rate and How long?)
                      3-pass beam,Take QE data, with dP=0%, Sieve In, Raster Off, Multi-Foil.    (Rate and How long?)
   Note: If too much electrons pounching through and making sieve holes unclear, we need to increase HRS momentum (D/Q3 has be to
         be scaled up or down with fix ratio), but it may also change the coverage of momentum,
         hence we may need to increase more than one time untill the data cover the whole acceptance (dP=+-4.5%).

c1) If the rate is still acceptable, we would better take an extra run of c) with Raster On, which can be used to check the quality of calibrated matrix,  but we can skip this if it takes too long time.

d) Momentum Scan: 3-pass, Elastic data, with LH target and mini raster on, sieve out, dP=+3%, 0%, -3%

The importance things to use this plan is a good estimation of rate and run time, and very quick online optics data quality checking.

Data being taken

We did take some optics data during our run period but I summurized those run and found that we actually don't have enough data to calibrate optics. [ https://hallaweb.jlab.org/wiki/index.php/R-HRS_Optics_Runs Data]

1,L-HRS

a) Vertex:   Run#2869 ~ 2876 with Multi-C, dP=0%. But we don't have single foil. The orginal Opitcs is good enough
   to see multi-foils so we can live with that.
b) Angle:    Run#2788,2788 with Multi-C,dP=0%, but Raster was ON. 
c) Momentum: Run#1229 ~ 1244, +2%,0%,-2%, E0=2.257, P0=2.055, Theta=16.5.

2,R-HRS

a) Vertex:   Run#1633 ~ 1643 with Multi-foils and Single-foil,dP=0%, but unfortunately,Raster was ON.
b) Angle:    Run#1735 ~ 1739 with Multi-foils and Single-foil,dP=0%, but unfortunately again,Raster was ON ...
c) Momentum: Run#1351 ~ 1373, -4%,-2%,0%,2%,4%, E0=2.257, P0=2.107, Theta=14.0. Here momentum of RQ3
   is equal to RD, but currently we need to run RD up to 3.14 while RQ3 can only go to 2.8, so we can not 
   use this data to calibrate our momentum.