RPC Production Sung Keun Park Department of Physics

RPC Production Sung Keun Park Department of Physics KOrea DEtector Laboratory (KODEL) Korea University Seoul, Korea Young Jin Kim University of Illinois at Urbana-Champaign 2008 -09 -25 Muon Trigger Review 1

Contents 1. Overview of RPC detector production 2. Bakelite production 3. RPC gap production 4. RPC module frame and readout strip plane production 5. RPC half octant frame production 6. RPC factory at BNL 7. RPC module production 8. RPC half octant production 9. RPC production schedule 10. Summary 2008 -09 -25 Muon Trigger Review 2

RPC Detector Production Assembly and Installation Bakelite RPC Detector Parts Pan-Pla, Italy Bakelite manufacture (CMS bakelite vendor) Korea University, Korea RPC gap (CMS Endcap RPC gap vendor) Riva, Italy Bakelite cutting (CMS bakelite cutting company) CIAE, China RPC module frame and readout strip plane (CIAE has access to CMS frame/readout strip vendors) Hi-Tech Manufacturing, US RPC half octant frame General Tecnica, Italy Bakelite cleaning (CMS bakelite cleaning company) 2008 -09 -25 Nevis Lab. at Columbia University, US Electronics (use CMS RPC discriminator chip) Muon Trigger Review RPC Detector RPC factory, BNL, US Assemble & Test RPC modules Assemble & Test RPC half octants PHENIX, BNL, US RPC group: • Installation (help from PHENIX technicians) • Commissioning • Operation monitoring of RPCs 3

Flow of RPC Gaps and Parts for PHENIX frames and parts Korea gas cell route US BNL Italy China bakelite route ØBakelites are produced, cut, cleaned in Italy. ØGas gaps are produced at Korea University in Korea. ØRPC module frames & readout strip planes are procured in China (CIAE). ØRPC half octant frames will be produced at Hi-Tech Manufacturing in US. ØFinal assembly is done at BNL. ØFlow is exercised with prototype C and D. 2008 -09 -25 Muon Trigger Review 4

Bakelite Production and QA in Italy v. Pan-Pla has been producing bakelites for the most of trigger RPC projects. v. Bakelites for PHENIX RPCs has been produced for station 3. v. Production of bakelites for the CMS Endcap RPC appending project will be followed. QA for bakelites l. PHENIX requirements of bakelite (same specs as CMS) Øbulk resistivity of bakelites: average = 1 -6 1010 cm at 20 o. C Ø / average < 0. 5 Øbakelite thickness = 2 0. 1 mm ØSurface Roughness Ra < 0. 2 μm u. Measurement of the resistivity of bakelites §Use CMS instrument to measure the resistivity of bakelites. A lot of help from CMS people Paolo Vitulo: recommissioned CMS tool and acquired space at University of Pavia for QA, Paolo Baesso (University of Pavia) Ian Crotty (CMS Endcap RPC production coordinator) Giuseppe Iaselli (CMS RPC leader) CMS automated test tool • allow to measure 9 points of resistivity on bakelite at same time. 2008 -09 -25 Muon Trigger Review 5

Bakelite QA Result in Italy pistons for measuring resistivity bakelite plate conveyor belts Result of resistivity measurement by PHENIX group (July at University of Pavia) PHENIX RPC group for bakelite QA K. Barish, D. Kleinjan (UCR) R. Towell, P. Bailey (ACU) T. Kempel (ISU), A. Vossen (UIUC) Øfulfilled 252 out of 317 bakelites to the PHENIX requirements (same as CMS specs). Øenough for producing RPCs at station 3 and RPC prototype at station 1. 2008 -09 -25 Muon Trigger Review 6

Bakelite Cutting and Cleaning in Italy l. Riva: CMS RPC cutting company ØCompleted cutting of bakelites for the PHENIX RPCs at station 3 l. General Tecnica: CMS RPC cleaning company Ø Clearing bakelites for the PHENIX RPCs and the CMS Endcap RPC appending project. A lot of help from CMS people Giuseppe Iaselli: organized for prototype D cutting and bakelite cleaning (CMS RPC leader) Giuseppe Belli (University of Pavia) Ian Crotty (CMS Endcap RPC production coordinator) 2008 -09 -25 Muon Trigger Review 7

RPC Gap Production in Korea Responsible to Korea University Faculty: B. Hong, S. Park, K. S. Lee, K. -S. Sim Graduate student: H. H. Shim Technical Staff: J. H. Bae, B. D. Kim, C. S. Park silkscreen table Procedures Applying all the procedures and tools used for the CMS Forward RPCs 1. Graphite coating for RPC electrodes - Silkscreen method - Surface resistivity of electrode ranges from 50 to 200 k /square silkscreen - Dry of the silk in room temperature for 4 days 2. PET film coating for protection of graphite electrodes - 1 layer of 200 micron PET film - 1 extra layer of PET to be attached during the RPC assembly test silk ink drying silk ink storage - A serious caution is needed to avoid scratches, especially on HV side during handling and transportation. 2008 -09 -25 Muon Trigger Review 8

PET film insulation machine pluck and weld PET film machine control unit PET film Insulated bakelite 2008 -09 -25 Muon Trigger Review 9

RPC Gap Production in Korea (continue) 3. Cleaning of surfaces of bakelites - Cleaning with isobutylene-base thinner - Cleaning with IPA just before the gap assembly - No scratching on spacer positions 4. Gap assembly - 3 layers of metric tables for the assembly and glue curing - Glue curing time : 24 hours - Glue : DP 460, 3 M production - Selection of spacers : 2 mm 20 microns - Use spacer jigs for the location of spacers Accuracy of positions < 1 mm linseed oil tank 5. Oiling - Linseed oil + heptane (Ratio : 40 % + 60 %) - Polymerization with air Rate : 60 – 100 liter/h/gap Period : 72 – 96 hours Humidity : 40% linseed oil distribution panel 2008 -09 -25 Muon Trigger Review linseed oil tank with vacuum pump RPC gap storage for linseed oil coating 10

RPC Gap Production in Korea (QA) 5. Tests for pop spacers and leak (QA) - No pop spacer allowed at + 20 h. Pa - Gas leak : less than 0. 2 h. Pa drop for 10 mins at +20 h. Pa 6. Extra sealing of periphery of gaps with EVA glue along to stop leak current along the edge of gaps Current (μA) H. V test results for CMS RPC gaps 7. HV tests (QA) - Total period of test : 6 days 1. 5 days for gas circulation : 10 volume- circulation before applying HV to the gaps 0. 5 day at 8. 5 k. V to observe Ohmic currents 4 days at working voltage to observe the current behavior at the initial stage of gas operation - Selection criteria Current limit : 2. 0 µA for RPC 3 a 4. 0 µA for RPC 3 b 5. 0 µA for RPC 3 c begin end - If the behavior of the current shows a tendency of increasing reject (The current should show a stability for QA) Gap ID number 2008 -09 -25 Muon Trigger Review 11

RPC Gap Production in Korea (shipping) 8. Extra protection for PET surfaces - Protection from scratches for both sides 9. Shipping boxes - Loading gaps vertically inside the boxes. - Need 2 boxes to load 40 sets of RPCs. So, total 7 boxes needed for RPC 3 - Sizes of the shipping box Small size : RPC 3 a Medium size : RPC 3 b Large size : RPC 3 c - All the gas pipes should be fully open to adapt any sudden change of air pressure top view of shipping boxes 2008 -09 -25 Muon Trigger Review 12

RPC Detector Module Frame Production in China Production of detector module frames and readout strip planes is responsible to CIAE PHENIX RPC group Scientist: X. Li, S. Hu F. Zhou, S. Zhou Production site: Beijing Honeytech Co. honeycomb panel computer control honeycomb producing/cutting machines 2008 -09 -25 detector module frame Honeycomb panel: 5 mm Al honeycomb core in between 0. 5 mm 2 layer Al sheets Al frame: 16 x 16 mm 2 Al bar with modification for services Muon Trigger Review 13

RPC Detector Module Frame Production Procedure in China 1. make honeycomb panels 2. design in the computer 3. manufactured by program control 2008 -09 -25 Muon Trigger Review 4. production 14

RPC Readout Strip Panel Production in China Production site: Beijing Kedi Co. laminate 0. 1 mm mylar film on 0. 25 mm thickness readout strip panel at both side signal readout strip planes 2008 -09 -25 Muon Trigger Review 15

RPC Half Octant Frame Production (Prototype D) half octant skin (Al plate) half octant frame (Al C frame) RPC detector module patch panel half octant support frame (Al bar) detector module support brace (Al bar) 2008 -09 -25 Muon Trigger Review 16

RPC Prototype D Half Octant Frame Manufactured in China RPC half octant placed on half octant assembly table at the RPC factory in BNL l. All half octant parts are made of aluminum. l. Half octant contains three RPC modules. l. We found a competitive US company (Hi-Tech Manufacturing) for mass production. Ø Responsible to UIUC J. Blackburn (Engineer), E. Thorsland (Technician) C. Mc. Kinney (Graduate Student) N. Mucia, G. Deinlein, A. Burnap (Undergraduate Student) 2008 -09 -25 Muon Trigger Review 17

RPC Factory at Bldg. 912 in BNL gas distribution racks and bubblers electronics and H. V supply racks dark current test temporary RPC gap storage/module debugging table DAQ and data base computers cosmic ray RPC module test stand RPC module assembly table RPC module parts preparation area 2008 -09 -25 Muon Trigger Review spacer pop, gas leak test table 18

RPC Gap Storage and Half Octant Assembly Area Two large shelves for the storage of RPC gaps Plastic curtain will be installed around shelf. Temperature and humidity sensor/control unit will be installed. Humidified gas (e. g. nitrogen or argon) distribution system for storing half octants will be set up. Movable large table for half octant assembly 2008 -09 -25 Muon Trigger Review 19

RPC Group at RPC Factory UIUC: Y. J. Kim, A. Vossen (Postdoc) D. Northacker (Technician) R. Yang, B. Meredith (Graduate Student) ACU: R. Towell (faculty) K. Andrews, P. Bailey, A. Basye, T. Jones, D. Thomas (Undergraduate Student) Muhlenberg College: B. Fadem (faculty) C. Harper, D. Broxmeyer, T. Sodre, A. Caringi (Undergraduate Student) GSU: X. He (faculty) J. Ying (Senior Scientist) C. Butler (Technician) K. Dayana, C. Oakley (Graduate Student) Korea University: B. I. Kim, K. B. Lee (Graduate Student) UCR: D. Kleinjan (Graduate Student) RBRC: R. Seidl (Scientist) 2008 -09 -25 Muon Trigger Review 20

Education and Training Graduate/undergraduate students are actively participated to RPC detector assembly and test. 2008 -09 -25 Muon Trigger Review 21

Incoming QA at BNL Incoming QA for RPC gap and module frame RPC gap (follow same procedure as Korea Univ. ) spacer position template on RPC gap l. Gas leakage test: Monitor pressure change over 30 min. and accept the gap has less than 5% change. l. Spacer pop test: gas leakage/spacer pop test Put spacer position marked template on top of RPC gap and press each spacer position. If spacer bonding is broken, pressure gauge shows large variation. Allowance 2. l. Dark current (all measured values are recorded into data base) Allowance: 5 A at 9. 5 k. V (same criteria at Korea University and compare to their values) dark current test monitor RPC module frame l. Visual inspection and measure dimensions. ØPut all values into database. example of PHENIX RPC database ØCompare to design values. 2008 -09 -25 Muon Trigger Review 22

RPC Detector Module Production at BNL lay down Mylar foil Prepare all RPC detector parts 8 mil Mylar foil, 5 mil Cu foil Readout strip plane with transition card Polyethylene gas tube, Ground bus cable CPE H. V cable, Kapton tape, Cu tape, etc. RPC detector module assembly procedure • Clean honeycomb panels and Al frames lay down Cu foil • Attach Al frames to bottom honeycomb panel • Lay down Mylar foil • Lay down Cu foil • Attach Mylar foil on H. V side at bottom RPC gap • Connect Polyethylene gas tube to bottom RPC gap • Place bottom RPC gap into detector module housing • Connect CPE cable to H. V cable on bottom RPC place bottom RPC gap into gap detector module housing 2008 -09 -25 Muon Trigger Review connect Polyethylene gas tube to bottom RPC gap connect CPE cable to H. V cable on bottom RPC gap 23

RPC Detector Module Production at BNL (continue) • Put readout strip plane on top of bottom RPC gap • Solder ground cable to ground bus cable • Attach Mylar foil on H. V side at top RPC gap • Connect Polyethylene gas tube to top RPC gap • Place top RPC gap into detector module housing • Connect CPE cable to H. V cable on top RPC gap • Wrap Cu foil over top RPC gap • Attach all ground cables (from CPE H. V cables, ground bus cables, and RPC gaps) to octant boundary Al frame • Solder the other end of ground bus cable on Cu foil • Lay down Mylar foil • Put top honeycomb panel and close it with screws put readout strip plane on top of bottom RPC gap solder ground cable to ground bus cable place top RPC gap into detector module housing complete RPC module wrap Cu foil over top RPC gap attach all ground to octant boundary Al frame 2008 -09 -25 Muon Trigger Review 24

RPC Detector Module Test cosmic ray trigger (10 scintillators readout both sides) 10 shelves for RPCs NIM crate with DAQ 3 PHENIX RPC TDCs within crate cosmic ray trigger (12 scintillators readout both sides) cosmic ray test stand at RPC factory l. We are measuring: Noise rate, Total (2 D) and strip efficiencies, Position and time resolutions, Cluster size 2008 -09 -25 Muon Trigger Review 25

RPC Detector Module QA Results (with PHENIX electronics) RPC test stand event display cosmic ray trigger scintillators RPC readout strip planes RPC H. V = 9. 7 k. V cosmic ray trajectory Noise rate: Noise Rate (Hz/cm 2) RPC H. V = 9. 4 k. V PHENIX RPC FEE Threshold = 200 m. V 2008 -09 -25 Muon Trigger Review 26

RPC Detector Module QA Results (with CMS FEE board) software threshold set to 3. 6 m. V Total efficiency = 95% RPC Strip Timing Resolutions: RPC H. V = 9. 4 k. V, CMS RPC FEE Threshold = 220 m. V New test with PHENIX electronics is on going. 2008 -09 -25 Muon Trigger Review 27

RPC Half Octant Assembly RPC prototype D 2 module patch panel Exercising half octant assembly took a place several times. Updating documentation of half octant assembly is in progress. We will start first half octant assembly on September 29 th. RPC module support braces half octant frame place for RPC prototype D 3 module place for RPC prototype D 1 module half octant assembly procedure documentation FEE panels 2008 -09 -25 Muon Trigger Review 28

RPC Half Octant QA QA at RPC factory, check/fix vgas leakage of RPC detector modules vany problem with H. V and L. V vall electronics and detector performance QA after installation to PHENIX, check vgas leakage of RPC detector modules vdamage of H. V and L. V connectors vdamage of signal cables v. RPCs with cosmic ray test runs 2008 -09 -25 Muon Trigger Review 29

RPC Production Schedule RPC prototype D (two half octants for run 9) ØRPC detector module assembly: complete ØRPC half octant assembly: 2008 September 29 th – October 12 th RPC station 3 ØRPC detector module assembly for north muon arm: 2009 January – June ØRPC half octant assembly for north muon arm: 2009 April – July ØRPC detector module assembly for south muon arm: 2009 May – October ØRPC half octant assembly for south muon arm: 2009 August – November RPC station 1 ØRPC detector module assembly for north muon arm (RPC 1 a): 2009 June – October ØRPC octant assembly for north muon arm (RPC 1 a): 2009 October – November ØRPC detector module assembly for north muon arm (RPC 1 b): 2009 July – November ØRPC octant assembly for north muon arm (RPC 1 b): 2009 November – December ØRPC detector module assembly for south muon arm (RPC 1 a): 2009 July – November ØRPC octant assembly for south muon arm (RPC 1 a): 2009 December – 2010 January ØRPC detector module assembly for south muon arm (RPC 1 b): 2009 July – December ØRPC octant assembly for south muon arm (RPC 1 b): 2009 December – 2010 January 2008 -09 -25 Muon Trigger Review 30

Summary We have completed to produce RPC prototype C and D modules. Ø 3 prototype C and 9 prototype D modules ØPrototype test is on going with PHENIX electronics. ØProduction chain is close to follow CMS and it is checked by production of prototype C and D. ØObtain a lot of experience for RPC detector production. ØGain operation and test skills of RPC detector. Mass production is started. ØBakelites for RPC station 3 are produced and cut. ØWe have almost complete procedure for producing RPC detector. ØWe have a complete RPC detector production schedule. 2008 -09 -25 Muon Trigger Review 31