1. Polarization Measurements of RHIC-pp RUN05 Using CNI pC-Polarimeter Itaru Nakagawa (RIKEN/RBRC) On behalf of CNI Polarimeter Group I.G.Alekseev A A.Bravar B G.Bunce B S.Dhawan D R.Gill B H.Huang B W.Haeberli E G.Igo F O.Jinnouchi V.P.Kanavets A K.Kurita H A.Khodinov J Z.Li B Y.Makdisi B A.Nass B W.Lozowski I W.W.MacKay B H.Okada G S.Rescia B T.Roser B N. Saito G H.Spinka L D.N.Svirida A D.Underwood L C.Witten F T.Wise I J.Wood F A.Zelenski B RBRC ITEP A BNL B ANL C Yale U D Wisconsin U E UCLA F Kyoto U G Rikkyo U H Indiana U I StonyBrook U J IUCF K Argonne U L Itaru Nakagawa (RIKEN/RBRC) On behalf of CNI Polarimeter Group I.G.Alekseev A A.Bravar B G.Bunce B S.Dhawan D R.Gill B H.Huang B W.Haeberli E G.Igo F O.Jinnouchi V.P.Kanavets A K.Kurita H A.Khodinov J Z.Li B Y.Makdisi B A.Nass B W.Lozowski I W.W.MacKay B H.Okada G S.Rescia B T.Roser B N. Saito G H.Spinka L D.N.Svirida A D.Underwood L C.Witten F T.Wise I J.Wood F A.Zelenski B RBRC ITEP A BNL B ANL C Yale U D Wisconsin U E UCLA F Kyoto U G Rikkyo U H Indiana U I StonyBrook U J IUCF K Argonne U L

2. Polarimetry: Impact on RHIC-SPIN Physics Asymmetries Single Spin Asymmetries Double Spin Asymmetries Polarization measurement by Elastic pp/pC Polarized proton Recoil carbon 90º in Lab frame Carbon target P beam Required Accuracy ~5%

3. pC Analyzing Power A N (100GeV) L. Trueman hep-ph/0305085 Recoil Carbon Need to Measure Recoil Energy t-dependence

4. RHIC Polarimetry

5. Characteristics of pC polarimeter Large Cross Section Solid target 20 sec./measurement for ~ 2% statistics. Immediate feedback to accelerator operation “Bunch by Bunch” beam polarization structure Polarization profile measurement  High Event Rate

6. pC Polarimeter Setup Ultra thin Carbon ribbon Target (3.5  g/cm 2 )1 3 4 5 6 2 Si strip detectors (TOF, E C ) 18cm 10mm 2mm pitch 12 strips 72 strips in total 1 3 4 5 6 2 45 deg Physics 1 3 4 5 6 2 90 deg Physics Physics asymmetry 1 3 4 5 6 2 1 3 4 5 6 2 Up-Down (Radial) Cross (Forbidden) False asymmetry   Redundancy  Systematic/Consistency Check Redundancy  Systematic/Consistency Check

7. Strip by Strip Consistency  2 Distribution of sin(  ) fit –Well Distributed around 1 –Evidence of Consistent Polarization Measurements by individual strips

8. Carbon Target L Energy Correction T deposit (keV ） ) Time of Flight t meas [ns] (adc)(DeadLayer) (t 0,  x )  Kinematic Fit

9. Energy Correction (Stability) Stability Error  9 ~ 11  g/cm 2 Stability Error  9 ~ 11  g/cm 2

10. Online/Offline Polarization

11. Run5 Polarization Profile 2mm Polarization Count Rate[Hz] Polarization

12. Uncertainties & Summary Energy Scale3~4 % Event Selection1% Polarization Profile Normalization from Run48.5% Total (Absolute)~ 9% Relative Run5Smaller

13. Backup Slides

14. Azimuthal Angle Distribution Fill Number  angle [deg.] Fill Number  angle [deg.]  = 0 deg.

15. Energy Correction Typical Thickness 〜 50  g/cm 2 Kinetic Energy = ４００ keV Correction Observation Energy Loss [keV]

16. Event Selection Dependence 2  vs 3  Cut Consistency  Systematic Error 22 33

17. Event Selection Error Event Selection Error ~ 1% ( was 3% in Run3,4) Event Selection Error ~ 1% ( was 3% in Run3,4)

18. Strip by Strip Consistency ~ sin(  ) fit ~13 4 562 2mm pitch 12 strips

19. Road Map to Finalize the Analysis Remaining Major Items –Continue QA (3 weeks) Suspicious bunch, strips –Study Off-Centered Target Measurements(2 ~ 4weeks) Fill by Fill Analysis Polarization Profile –Normalization with Jet (4 weeks)

20. Energy Correction (Strip by Strip Consistency) Strip Number （７２ Total ） Energy Correction(  g/cm 2 ) All Detectors are made from same wafers  Any inconsistency should be accounted as  sys

21. Energy Correction (Strip by Strip Consistency)

22. Systematic Error Summary(1) BlueYellow Energy Calibration--- strip-by-strip consistency 3.5 (1)4.5 (2) Event Selection33 Stability9.011.1 Total10.1 (9.1)12.3 (11.3) Energy Correction [ug/cm 2 ] ( ):Relative Error

23. Contents Kinematics Reconstruction –  source energy calibration –Deadlayer energy correction –Systematic error estimation(1) Polarization (1st Path Analysis Results) –Online/Offline –Event selection 2  /3  –Strip by strip consistency  sin(  ) fit –Systematic error estimation (2)