1. The Progress of PHENIX RPC Production in China Shouyang HU Xiaomei LI Shouyang HU Xiaomei LI Science and Technology on Nuclear Data Laboratory China Institute of Atomic Energy 2011. 08

2. Outline 1.Motivation of the PHENIX Forward Upgrade 2.The Start of PHENIX-RPC in China 3.Laboratory Construction and RPC Production at CIAE 4.Position Sensitive RPC R&D 5. Summary

3. 1. Motivation of the PHENIX Forward Upgrade

4. W production at PP collision (a) (b)

5. PHENIX Forward Upgrade Add RPC ( Resistive Plate Chamber) as a fast muon trigger to study the quark-gluon structure of the proton by observing W-bosons from colliding polarized proton beams at RHIC..

6. 1.a fast online measurement of the muon momentum to reject low momentum muons from hadron decays in jets 2.on a coarse timing measurements to remove background correlated with the incoming proton beam bunches. PHENIX Forward Upgrade

7. PHENIX Trigger Needs Design Luminosity √s = 500 GeV σ=60mb L = 2x10 32 /cm 2 /s Total rate ＝ 12MHz DAQ LIMIT =1-2kHz （ for μ arm ） Required RF ~ 10,000 ) RF~ 250-500 (√s= 200 GeV ) is inadequate

8. 2.The Start of PHENIX-RPC in China

9. First RPC Prototype Made by PKU in 2005 Size: 43×43 × 0.6 cm 3 Graphite coat: 40 × 40 cm 2 Double gas-gaps: 2 mm each Read-out strip placed between the two gas-gaps bakelite resistivity: ~ 10 10 - 10 12  cm

10. Beam Test at RHIC Run5 RPC1 RPC2 RPC1 Grounded to Platform RPC2 Grounded to MUID Gas Panel

11. Pre-QM2006 PHENIX Collaboration Meeting in Suzhou

12. The Tasks of PHENIX Groups GSUUIUC Korea Uni.CIAE Prototype Development & QA Gas mixing Position resolution Chamber Production R&D Module Parts Assembly & QA

13. 3.Laboratory Construction and RPC Production at CIAE

14. Main goals: Train students and technicians for future QA and assembly Test prototypes Research & Development Laboratory construction at CIAE

15. Prototypes made by CIAE (No.1) Two prototypes: resistivities The resistivities of the bakelites of prototypes are around 10 12  cm. The sizes are same as PHENIX RPC2A design.

16. Prototypes made by CIAE (No.2) The upstream of Prototype No.2 is separated into two parts and the readout strips are jointed with ground by matched resistances.

17. The Way to Improve RPC Time Resolution 1.S urface smoothness of bakelite and Graphite coat 2. The choice of bakelite resistivity 3. The ratio of gas mixture &HV 4. The design of readout electrode PHENIX reqirement:2.0ns Our Prototype:1.5ns in average

18. Supporting layers The RPC test multilayer ： 2.0×1.0×0.8 m 3, 9 detector supporting layers in total, can test 5-7 RPCs at the same time.

19. Has equipped gas system, electronics and DAQ system. Gas System and Electronics

20. The Set-up of RPC Muon Test

21. Comparing the Signals from Avalanche Mode and Streamer Mode Avalanche mode Streamer mode RPC working voltage=9800V RPC working voltage=10200V The chambers have high noises from 9000V to 9800 V

22. Time Resolution Test at CIAE We changed HV and the ratio of the gases to study time resolution. For different gas mixtures, we got best time resolutions at different HVs. The HV of the best resolution moves ahead as the ratio of SF6 increases

23. Production of RPC for PHENIX CIAE has made 7 batchs of RPC module parts including box, readout-strips and support frame for PHENIX. On time with high level

24. Installation of RPC detectors at PHENIX Summer 2009+2010 Summer 2012 Summer 2014 RPCRPC RPC 3 North & South RPC 1 North & South RPC 2 North & South? Time Line

25. Acknowledgement from PHENIX Project Manager

26. Awards RPC R&D and productions+Simulations (Direct photon, heat capacity) We published 12 papers finished by CIAE alone and 30 papers collaborted with PHENIX on RHIC physics during last four years. Award:First Prize in Scientific and Technological Achievement Award at CIAE applying for Awards: Award of CNNC (China National Nuclear corporation)and Award of Peking.

27. 4.Position Sensitive RPC R&D

28. The design of position sensitive RPC 1. A crossing in the shape of an “X” of readout strips. 2.Two working modes(Avalanche & Streamer)

29. Prototype of Position Sensitive RPC

30. Summary China group participates PHENIX Forward Upgrade. CIAE made RPC R&D and 7 batches of RPC module parts for PHENIX, which have been installed in PHENIX. We are also making data analysis on pi0. R&D of Position sensitive RPC We acknowledge the support of NSFC.