1. PHENIX W-Boson Trigger Itaru Nakagawa RIKEN/RBRC On behalf of RPC/MuTrig-FEE Collaboration

2. sqrt(s)=500 GeV @ RHIC  Parity Violation Asymmetry Clean flavor separation w/o fragmentation uncertainty

3. Expected Asymmetries @ PHENIX Full Detector Simulation S/B ~ 3/1 Assumed 319 pb -1 and 1320 pb -1

4. Flavor Separation by A L W +/- ∫Ldt=800pb -1, P=0.7 projected @500GeV Expected Sensitivity with W measurement

5. Trigger Rate @ sqrt(s) = 200 GeV 100 GeV  -Trigger Rate < 2 kHz

6. Trigger Rate @ sqrt(s) = 500 GeV 250 GeV Rate ~ 12 MHz !! Design Luminosity √s = 500 GeV σ=60mb L = 2x10 32 /cm 2 /s Rejection Factor ~ 10000 

7. Rejection Power : Approach 50 25 Momentum GeV/c P T Sensitive Trigger Does The Job W W

8. RPC1(a+b) MuTr St. 1 RPC2 High - P T Trigger Algorithm Trigger Logic B

9. R1(a+b) R2 R3 r=3.40m MuTr (I)Three dedicated trigger RPC stations (CMS design): R1(a,b): ~12mm in , 4x θ pads R2: ~5.4mm in , 4x θ pads R3: ~6.0mm in , 4x θ pads (Trigger only – offline segmentation higher) NSF (Funded) JSPS (Funded) (II)MuTr front end electronics Upgrade to allow LL1 information Rejection ~12,000, beam background immune. PHENIX Muon Trigger Upgrade

10. 10 A. Basye, D. Isenhower, D. Jumper, N. Sparks, R. Towell, C. Watts, J. Wood and R. Wright Abilene Christian University, Abiline K. Barish and R. Seto University of California, Riverside S. Hu, X. Li, F. Zhou and S. Zhou CIAE, Beijing, China A. Linden-Levy, E. Kinney, J. Nagle University of Colorado, Boulder C.Y. Chi, W. Sippach and W. Zajc Columbia University and Nevis Laboratory, New York C. Butler, K. Dayana, X. He, C. Oakley and J. Ying Georgia State University, Atlanta J. Blackburn, M. Grosse Perdekamp, C. Lee, Y.-J. Kim, B. Meredith, T. Natoli, N. Mucia, D. Northacker, J.-C. Peng, E. Thorsland, A. Veicht, A. Vossen and R. Yang University of Illinois, Urbana Champaign J. Hill, T. Kempel, J. Lajoie, G. Sleege, C. da Silva and F. Wei Iowa State University, Ames J.H. Bae, B. Hong, B. D. Kim, B. I. Kim, K. B. Lee, K. S. Lee, C. S. Park, S. Park and K.-S. Sim Korea University, Seoul, Korea B. Fadem, J. Herstoff and P. Lichtenwalner Muhlenberg College, Allentown, PA 18104, USA Y. Mao and R. Han Peking University, Beijing, China G. Bunce and R. Seidl RIKEN BNL Research Center RPC Collaboration

11. PHENIX muon trigger RPC 2007-10-13 11 Design and R&D for the PHENIX Muon Trigger RPCs Characteristics of RPC Fast response o Suitable for the trigger device Good time resolution: 1-2 ns Good spatial resolution: typically ~ cm o Determined by the read-out strip width and cluster size Low cost Typical gas mixture o 95% C 2 H 2 F 4 + 4.5% i-C 4 H 10 + 0.5% SF 6 Efficiency  95% Time resolution  3 ns Average cluster size  2 strips Rate capability0.5 kHz/cm 2 Number of streamers  10 % PHENIX RPC detector requirement RPC station 3 at north muon arm

12. All TDC widths are less than 3 ns. First RPC Prototype C Test Results Cluster size seems constant from 9.3 to 9.5 kV. First efficiencies ~95% at 9.5 kV. R.Seidl: W physics 12 RSC meeting, April 21

13. 13 ► Bakelite produced and cut in Italy ► Gas gaps are produced at Korea University ► RPC frame & parts are procured in China (CIAE) ► Final assembly done at BNL. Manufacturing of RPC Gaps and Parts for PHENIX  Tested Successfully with Prototype C bakelite route gas cell route frames and parts Korea BNL China Italy

14. Gas Gap Production at Korea University (prototype C, presently prototype D) R.Seidl: W physics 14 RSC meeting, April 21

15. 15 R.Seidl: W physics RSC meeting, April 21 Assembly of the first (of three) Prototype C

16. MuTrig-FEE Collaboration

17. MuTR FEE Upgrade Readout Analog Signal to Get the Position of Particle Passage (OFFLINE Analysis) Get Digital Signal for Trigger Decision (ONLINE) Readout Analog Signal to Get the Position of Particle Passage (OFFLINE Analysis) To trigger Logic ADC 0.9Q 0.1Q Q 1.Minimum deterioration to existing MuTR performance 2.High/reliable triggering efficiency Bottom Line

18. 18 Existing FEE MuTR (Station-2) Prototype Test SetUp ~2007 September~ AD Board TX Board

19. Noise Performance FEE Pedestal RMS:1~2 ADC ch  ~ 1% of Most Probable Value 100  m resolution Without New Electronics Additional Noise ~ 20%

20. PHENIX W-Trigger Schedule (Run08) RPC2 RPC3 FEE2 FEE3 FEE1 South Arm : Half Octant FEE2 FEE3 FEE1 Absorber

21. PHENIX W-Trigger Schedule (Run09) RPC2 RPC3 FEE2 FEE3 FEE1 FEE2 FEE3 FEE1 RPC2 RPC3

22. PHENIX W-Trigger Schedule (Run10) FEE2 FEE3 FEE1 FEE2 FEE3 FEE1 RPC2 RPC3 RPC2 RPC3

23. PHENIX W-Trigger Schedule (Run11) FEE2 FEE3 FEE1 FEE2 FEE3 RPC2 RPC3 RPC2 RPC3 RPC1(a,b)

24. Summary W Single Spin Assymmetries as Quark/Antiquark helicities  -Trigger Upgrade Necessary for W Detection P T Sensitive Trigger  Factor 10000 Rejection RPC(NSF) and FEE-Upgrades (JSPS) Funded Designed performances were already demonstrated by Prototypes NorthSouth MuTrig-FEE Run08Run09 RPC Run09Run10

25. Backup Slides

26. Upgrade Schedule 2002200320042005200620072008200920102011 MPC VTX (barrel) FVTX NCC MuTrigger R&D PhaseConstruction Phase Ready for Data

27. System overview 27

28. PHENIX Design Efficiency  95% Time resolution  3 ns Average cluster size  2 strips Rate capability0.5 kHz/cm 2 Number of streamers  10 % PHENIX RPC detector requirement Our requirements are Very similar to those Of the CMS end caps. Therefore we are taking advantage of their work. Thanks!