1. RHIC CNI Polarimeter status RHIC CNI Group February 26, 2008

2.  2 /ndf = 6.5/6 33 Hours, 10 stores, 1.4M events Statistics uncertainty only Rough event selection TOF width cut (+/- 10nsec) Channel 2-3 width selection No background correction. HJet: Blue1

3. Fill#H-Jet Events 988550427 988894430 989037767 989772279 9898176010 990121035 9902162664 9905179075 9906358828 9909213666 total1366181 P BLUE =0.486  0.023

4.  2 /ndf = 1.9/6 25 Hours, 3 stores, 1.4M events (Feb. 24-26) Statistics uncertainty only Rough event selection TOF width cut (+/- 10nsec) Channel 2-3 width selection No background correction. HJet: Blue2

5. Fill#Events 9942472968 0.431  0.040 9948401223 0.387  0.042 9949523399 0.409  0.036 total1397590 0.415  0.023

6. HJet: Yellow P YELLOW =0.384  0.021 Fill#H-Jet Events 9919215906 9920282587 9935213772 9937261714 9938353033 9939362811 total168923

7. HJet: Yellow  2 /ndf = 9.8/6 31 Hours, 6 stores, 1.7M events Statistics uncertainty only Rough event selection TOF width cut (+/- 10nsec) Channel 2-3 width selection No background correction.

8. pC: Online Polarizations Only scan measurements at store Measures average polarization over trans. profile This is what directly (should) relate to HJet measurements, but… Absolute scale in not yet fixed A N from Run4! Latest fills not yet included

9. pC: averaging Mainly in blue: Intensity profile is flat  we stay longer at beam center than at periphery  measured polarization is closer to P max than to /P max ~ 0.93 for blue, see next slides Yellow looks fine for this Latest fills not yet included

10. Polarization Profile   P(L/L max ): just an example If there are problems with target position determination  Exclude position from calculations: R=0.29  0.07 Latest fills not yet included

11. Polarization Profile R vs fill ~ 0.28 /P max ~0.88 ~ 0.16: /P max ~ 0.93 Run5/6: R~ 0.10  0.15 Latest fills not yet included

12. pC vs Hjet HJet-yellow HJet-blue P online (pC)/P(Jet)=1.06  0.06 -1%: C energy correction and cuts (online/fast_offline difference) +7%: change in A N A N from Run4! P online (pC)/P(Jet)=1.17  0.06 +6%: from “bad” scans in this period (flat intensity profiles) +4%: C energy correction and cuts (online/fast_offline difference) +7%: change in A N A N (Run5)/ A N (Run4) ~ 1.01 A N (Run6)/ A N (Run4) ~ 1.15 Latest fills not yet included

13. Fast offline, normalized to HJet Normalization uncertainty (stat. only) Feb 23Feb 14 Latest fills not yet included

14. Summary HJet demonstrates very stable/consistent measurements Consistent target asymmetry vs -t (with the same target polarization) Same (and even lower in Run8) background level pC data Polarization profile in blue is similar to Run5/6; polarization profile in yellow is sharper Experiments see more polarization than HJet due to intensity squared weighting: by 7%-relative in blue and by 12%-relative in yellow (if vertical and horizontal profiles are the same!) Blue-online polarizations are overestimated by (17  6)%-relative +7% - from A N (compared to Run4) Yellow-online polarizations are overestimated by (6  6)%-relative +7% - from A N (compared to Run4)

15. Backups

16. Hjet: Background level 1.2 <T R <2.5 MeV, 2 hours data YELLOW mode BLUE mode BPM at IR12 reading: Blue (x,y)= (+5, +8)mm Yellow (x,y) = (0,  4)mm, Fill#9920 BPM at IR12 reading: Blue (x,y)= (0,  4)mm Yellow (x,y) = (  10, +10)mm, Fill#9905

17. pC: Online vs “fast offline” Yellow online polarizations look unbiased compared to online Blue online polarizations are overestimated compared to online by ~4% relative Absolute scale in not yet fixed

18. pC stability: “Dead Layer”

19. pC stability: T0