LEFT_HRS& BitBite

1. Presentation by Tai 2012/15/5 LEFT_HRS& BitBite

2. RHRS Optics? Timing?(Igor finish?) VDC t0 PreShower/Shower (not applicable) LIST • LHRS • Optics (report shortly) • Almost complete with dp not finalized • Timing (report shortly) • VDC t0 • CER adc offset&gain • PRL adc offset&gain • Efficiency

3. MWDC T0 Time-to-Distance Conversion Relative wire position Tracking help etc.. LIST • BIGBITE • Optics • Trigger Plane • ADC (offset &gain) • TDC (offset)

4. LHRS-->Timing Result • Define: TOF = (s2time-s1time)-(s2pathl-s1pathl)/(0.3m/ns) • With mean = -0.22 ns and sigma = 0.59 ns

5. Timing Process • 1. Calibrate the left/right tdc pmt separately • diff = LT[i] – LT[i+1], where we require hit in both bars (t_pad[0] = i, t_pad[1] = i+1) • Align the “diff” value to zero using the middle bar as the reference. • 2. Calibrate left/right tdc required hit in the mid-plane. This will give a constant offset to one side.

6. Timing Process • 3. Check diff time between bar each plane separately. • i.e. S1 time diff (left) and S2 time diff (below)

7. Timing Process • 4. Now check the time difference between plane. Adjust additional offset to align beta = v/c = p/E = 1 for electron selection cut.

8. Optics • 4 reconstructed variables (dp,phi,theta,y) • Each variable can be calculated for its transform matrix independently.

9. Optics • Vertex: Using run 1237 as the best match for survey for mispointing to the center. At 16.5 deg.Dz = 2.31 mm, Dy = 0.54 mm • Result: sigma (2.78 - 3.89 )mm • peak 0 mean 148.41 mm sigma 2.93 mm • Peak 1 mean 123.33 mm sigma 3.20 mm • peak 2 mean 98.41 mm sigma 3.32 mm • peak 3 mean 73.60 mm sigma 3.12 mm • peak 4 mean 49.27 mm sigma 3.59 mm • peak 5 mean 24.59 mm sigma 2.78 mm • peak 6 mean 0.42 mm sigma 2.85 mm • peak 7 mean -24.57 mm sigma 3.89 mm • peak 8 mean -49.19 mm sigma 3.93 mm • peak 9 mean -74.02 mm sigma 3.23 mm • peak 10 mean -99.42 mm sigma 4.60 mm • peak 11 mean -124.69 mm sigma 3.36 mm • peak 12 mean -149.38 mm sigma 3.15 mm

10. Optics • Check other runs with different L_theta and/or with sieve. • The example of the sieve data for run 1234 • vertex • peak 0 mean 72.56 mm sigma 3.83 mm • peak 1 mean -74.63 mm sigma 3.26 mm • vertex vs ph

11. Optics • Sieve: using Optics-C (13foils) run 1238

12. Optics • The Sieve data is used twice for both theta and phi reconstruction. • Hence, twice carefully hole selection and cut have to be made. • (Sieve reconstruction for dummy 15 cm)

13. Sieve reconstruction • Sieve X = X_tg+L*theta_tg • Sieve Y = Y_tg +L*theta_tg • L = distance to Sieve from Hall center

14. Unfortunately, I cannot make the code work yet. :'( Waiting for help from others Optics • OPPS!! • One more thing left • Momentum dp

15. To calibrate the ADC for the trigger plane is not as simple as the cer &/ll Prl. The offset is adjusted using LA/RA raw The gain factor is much more trouble. BigBite • Trigger plane Calibration • TDC (not yet) • ADC

16. 1. gain match left and right PMT on the same bar 2. gain match each bar BigBite • As we need the result to reflect a good • dE vs E energy deposit • Where dE energy is calculated from sqrt(LE*RE) • So ....

17. BigBite • Ideally we want LE = RE. • First I rotate LE vs RE by 45 degee which become LE-RE vs LE+RE • The slope(m) will yield the change we need • (1-m)LA = (1+m)RA

18. BigBite • This is the result of LE vs RE after calibration for plane e pad #10

19. Plane dE: sqrt(LE*RE)(black),LE(blue),RE(red)

20. Plane E: sqrt(LE*RE)(black),LE(blue),RE(red)

21. BigBite • So we have the gain match for left/right PMT on the same bar done. (except bar #1 plane dE) • LE vs RE for dE plane with LH2, 400 MeV • Left are uncorrected one. Right are corrected value.

22. BigBite • Same plot for E plane.

23. BigBite • I am at the point to determine method to use to aline gain factor relative to each bar. • Option 1: • Using data from PSTAR to construct the possible energy lost in dE vs E plane • (figure on the left)

24. This is the 400 MeV LH2 elastic run. As seen, the dEvsE is not yet good.

25. Bitbite • Option 2 • Graphic cut area for each Energy blob and create itself pattern? • Any suggestion??