Resistive Plate Chambers in CMS INFN GR1 19 September 2002 G. Iaselli

Introduction Five wheels RB4 …… 120 chambers RB3 …… 120 chambers One barrel sector 60 sectors in total

Production flow Italy China Bulgaria Responsibility of Bari group Bakelite production and quality control Mechanics for RB1 RB1 Assembly and test Gap production and quality control Front-end production Bulgaria RB2, RB4 assembly and test Mechanics for RB2, RB3, RB4 RB3 Assembly and test Responsibility of Bari group Responsibility of Pavia group

Gap and double gap QA I Gaps Accept gap if: Controls: no gas leakage “gas leakage test” over-pressure test up to 20 mbar current vs HV in pure C2H2F4 Accept gap if: no gas leakage all spacer properly glued I (8000 V) < 5 mA Over 175 gap produced so far, 24 have been dropped, mainly due to bad gluing of the spacer Yield = 86% I Gaps

Gap and double gap QA Needed manpower: Controls: Electrical contiguity between strips and kapton Shorts between strips Gas leakage I vs HV Only 1 DG (out of 50) has been dropped for a short between two strips Needed manpower: two technicians + supervisor

Chamber assembly 1) Position double gaps 2) Cooling pipe installation and test of the circuit up to 20 bars 3) Gas pipe installation and leakage test for each double gap 4) Position front-end boards 5) Cable the low voltage and slow control circuits 6) Check the front-end/kapton connectivity

Chamber assembly 24 RB3 W0 assembled Needed manpower: 7) Insert lateral profiles 8) Leakage test for the whole chamber 9) Electrical test of the LV circuit 10) Close the chamber with the aluminium covers Needed manpower: two technicians + supervisor 24 RB3 W0 assembled

Chamber test Needed manpower: Major hardware and software developments has been carried out to prepare the test area: VMS home built TDC special floating HV/LV supply Object Oriented on line system Data base Currents vs HV Rates (strip by strip) Global efficiency Needed manpower: two physicists + technician

Protocol for chamber test: conditioning A LabView programme allows to automatically control the CAEN SY1527 Procedure: The chambers are fluxed with gas for 1 day First HV cycle: the voltage is increased by 1 kV every 15 min. At the end the HV is fixed to 8 kV After 5 hours the second HV cycle is repeated with an interval time of 5 min. For each chamber all information temperature, pressure, umiditity, currents) are registered and reported in DB

Protocol for chamber test: cosmics Collect ~ 5000 events At HV=8 kV Check the strip profile: Dead strips Time misalignment Disconnected cables or kapton

Protocol for chamber test: cosmics Trigger position A: the scintillators cover the forward RPC double gap. Collect ~ 10000 events at different HV. Monitor the chamber performance: Efficiency Cluster size noise At working plateau (HV=9.6 and 9.8kV) supply separately the up (and down) single gap and take data Trigger position B: the scintillators cover the backward RPC gaps. Repeat the procedure at point 2.

Chamber data base

Results of the test Currents vs HV Efficiency

Results of the test Rate 9.8 kV 9.6 kV 9.4 kV 9.0 kV Cluster size

Installation schedule Recent thunderstorm on the RPC performance originate from Babar have forced the experiments to revise the gap construction procedure This has introduced an almost one year delay on the project Wheel YB 0 September-December 2003 Wheel YB+2 January-February 2004 Wheel YB+1 September 2004 Wheel YB-1 May-June 2005 Wheel YB-2 June-August 2005 The CMS schedule Safe transportation of double gaps and chambers is expensive and difficult. Moreover Setting up the laboratories requires resources and intense collaboration from Italian physicists.

Original production scheme CMS had foreseen the chamber production distributed among : General Tecnica, assembly of RB2 and RB4 Sofia, assembly and test of RB3 Beijing, assembly and test of RB1 Bari, test of RB2 and RB4 Pavia, test of RB4 Due to some delay in the procurement of the material and in the setting up of the sites, this scheme is not feasible for the first wheel. Bari has already assembled, under the responsibility of a team from Sofia, RB3 W0 and is now starting with RB1 W0 RB2 and RB4 assembly at GT: Some delay for the area and tool preparation The site should be operative for September The first wheel will be assembled in Italy with the help of Sofia and Beijing Schedule for wheel 0 25 RB3 => end September 2002 (Bari + Bulgaria) 25 RB1 => end January 2003 (Bari + China) 25 RB2 => end March 2003 (Naples + GT) 25 RB4 => April 2003 (Pavia + GT)

Wheel 0 Three sites: Bari, Pavia, GT Five groups: Bari, Naples, Pavia, Sofia, Bejing RB3 assembly and test in Bari (teams from Sofia) RB1 assembly and test in Bari (teams from Bejing) RB2 assembly in GT (teams from Naples) RB2 test in Bari (teams from Naples) RB4 assembly in GT (teams from Bari/Pavia/Naples)) RB4 test in Pavia (teams from Pavia) China and Bulgaria maintain responsibilities for chambers construction, test and commissioning. Bari workshop operative - Gap production: 2 physicists full time Chamber assembly: 2 physicists full time + 1 engineer full time Chamber test: 3 physicists full time + 1 INFN fellowship + 1 PhD 4 technicians full time + 1 art. 23 + 1 art. 2222 2 technicians from mechanical workshop ( agreed with INFN) Pavia workshop operative in March 2003 - Chamber test: 2 physicists full time + 1 physicist 30% - 2 technician full time Help from INFN Electronic Pool GT workshop operative in September/October 2002 GT teams + Naples (2 physicists 100%, 2 technicians 80%)

Bari 6 staff physicists 1 PhD MURST felloship (assegno): Pugliese Abbrescia Colaleo* Iaselli Maggi Nuzzo Ranieri 6 staff physicists 1 PhD MURST felloship (assegno): Pugliese 1 INFN fellowship:Vankov 1 PhD: Cavallo 1 staff electronic engineer: Loddo 4 staff technicians full time: Clemente, Chiumarulo, Pinto, Papagni 1 art 23 (two years): Abadjiev 1 art.2222 (one year) 2 from technicians from mechanical workshop * Vincitrice di concorso

Naples/Pavia Naples 2 staff physicists : Paolucci,Piccolo 1 staff physicists 50%: Sciacca 1 technicians from electronic workshop (80 %) 3 technicians from mechanical workshop (80 %) Pavia 2 staff physicists full time: Vitulo, Torre 1 staff physicists 30%: Riccardi 2 staff technicians: Imbres, Vicini 1 engineer 30%:Belli 1 art. 2222 (?) Help from INFN electronic pool

Schedule at Pavia

Distribution of resources Bakelite production and QA at C.P. Belli, Vitulo, Imbres, Vicini highly involved; 1 shift (4/5 days) every two months. Gap production and QA at GT Abbrescia, Nuzzo, Chiumarulo, Pinto highly involved; Other persons from Bari are taking shifts; Teams from Naples and Pavia are taking shifts; 1 shift ( 2/3 days) every two weeks. Physicist and engineers Technicians

Distribution of resources Chamber assembly in Bari Clemente, Iaselli, Loddo, Ranieri, highly involved; Papagni, art. 2222, highly involved; Chiumarulo, Pinto , if not in GT; 2 persons from mechanical workshop 2/3 persons from Peking/Sofia supported by Italy Chamber test in Bari Cavallo, Colaleo, Maggi, Pugliese, Vankov highly involved; 1 technician (electronics) ?? Other persons from Bari should take shifts; Teams from Naples and Pavia should take shifts; 1 week shifts. Physicist and engineers Technicians

Distribution of resources Chamber assembly at GT Clemente, Papagni, Abadjiev, highly involved; GT team, Naples team. Chamber test in Pavia Torre, Vitulo, Imbres, Vicini highly involved; Riccardi@30% Help from INFN electronic pool; Physicist and engineers Technicians

Distribution of resources Cern Phase 1: stocking at ISR 1 Physicist + 2 technicians at Cern for chamber acceptance and test. People from Bari, Naples and Pavia Phase 2: Installation, 2 months in 2003 3 Physicist + 6 technicians at Cern

Wheel 0

Current status Bari: 24 RB3 assembled. Now under test. The assembly was done at a rate of 3/4 chamber/week. The presence of a team from Sofia has been crucial. The assembly of RB1 will start middle September. A team from Beijing will participate. Pavia: See schedule GT: Assembly hall not ready. Hopefully ready end of September.

Wheel  0 Distributed production in Italy Same as for wheel 0: More manpower needed per wheel: - two physicists for three months to Bari for RB3 (from Bulgaria/Cina) - two physicists for three months to Pavia for RB1 (from Bulgaria/China) Total of 12 months-men per wheel Production rate: 2.5 chamber/week, 10 chamber/month Test rate: 15 chamber/month Bari: RB3 Ass./test (Sofia), RB1 Ass./test (China), RB2 test (Naples) Pavia: some RB4 test , RB1 test (China) GT: RB4 Ass.(Bari), RB2 Ass. (Naples)

Wheel  0 Distributed production in Italy Other option: Subdivide production by dimension: 30 Ch (1500mm): Bari 26 Ch (2500mm): GT 24 Ch (2080mm): GT 16 Ch (2000mm): Pavia Produce under Naples responsibility RB2 in a local industry and move production of RB1 at GT

Wheel  0 Distributed production (Italy) External manpower needed per wheel: two physicists for three months for RB3 (from Bulgaria) two physicists for three months for RB1 (from China) total of 12 months-men per wheel total of 60 months-man (5 wheels) 1200 € /month…… 72000 € 1000 € /travel ……..20000 € (20 trips) total …………… 92000 € China and Bulgaria maintain responsibilities for chambers construction, test and commissioning.

Wheel  0 Additional resources needed in 2003-2006 Bari Conferma di 2 tecnici meccanici dalla Sezione Conferma di un tecnologo (80%) (Loddo) dalla Sezione 2 art 2222 fondi (FAI) Un art. 15 profilo elettronico Pavia Conferma 1 tecnico elettronico dalla Sezione 1 art. 2222 Napoli Conferma di 1 tecnico elettronico dalla Sezione

Wheel  0 Distributed production (world) Apply the scheme only for the production of the first two wheels which are demanding from the schedule point of view. Prepare the sites in Sofia and Beijing for chamber assembly and test. Worries on safe transportation, transport cost and budget capabilities remains. Situation could be revised middle 2003

Wheel  0 Concentrated production at GT Assembly all chambers at GT. Assembling of 240 chambers already foreseen (contract signed) Assembly additional 240 chambers at a cost of 270 € each total 65000 € Assume 10 chambers/month………..48 months!! Need to produce 20 chambers/month (1 chamber/day) to stay within 24 months. Space and schedule uncertain Chambers have to be sent to other sites for testing More institute manpower needed at GT for the assembly

Additional costs for gap production Bakelite 5 € /foil… (cutting)….17500 € Gaps 0.5 € /piece (pre-stamped gas inlet)…4000 € Manpower + material 5 € /gap……………….10200 € 3 € /strip……………… 3060 € 26 € /bi-gap………… 26520 € Tools 775 € /tool (30 gap frames)……… 23250 € 181 € /tray… (30 trays)…………… 5430 € 517 € / trolley (3 trolleys)…… … 2068 € Total 92028 € Update of the contract with GT?

Aging test The R&D is coordinated by Cern to help Atlas and CMS with the GIF logistic (source operation, gas system, ect, Many small gaps under irradiation. Some results at the next meeting of the RPC committee; Two MB1 will be send to GIF at the end of the month for a long term test; Some travel budget needed for the test; Some budget needed for the construction of the gas close loop system (negotiation with Cern under way, but about 10-15 kCHF may be needed)

MOFB (kCHF)

CORE

Richieste Napoli

Richieste Pavia

Richieste Bari

Alfonso Boiano1, Flavio Loddo2, Pierluigi Paolucci1, Antonio Ranieri2 RPC HV-LV project I.N.F.N. Naples Introduction System requirements and description SASY-2000 project Prototype tests Alfonso Boiano1, Flavio Loddo2, Pierluigi Paolucci1, Antonio Ranieri2 1) I.N.F.N. of Naples, 2) I.N.F.N. of Bari

Introduction I.N.F.N. Naples The idea of the HV-LV system for the RPC detector of the LHC experiments is to split the system in two: LOCAL: SY1527 mainframes placed in control room and a 48 Volts High Power Source; REMOTE: distribution system placed in the UXC zone around the detector. It consists of a 6U custom crate housing 2 independent controllers and up to 8 distribution board equipped with 4 HV + 8 LV floating channels. The system will work in very hard conditions due to the high magnetic field and high radiation environment. A common project (SASY 2000) to realize this system is going on between the I.N.F.N. and the CAEN company.

requirements and system description I.N.F.N. Naples requirements: system working in high magnetic field; system working in an high radiation environment; local system in control room + distributed remote systems on the detector; low voltage (48 Volts) running from the local to the remote system; floating HV (12KV–1mA) and LV (7V–0.42A (ana.) and 7V–0.9A(dig.)) channels (noise reduction). wheel 1 2 3 4 5 TOT gaps 408 2040 HV ch. 204 1020 front-end 936 4680 LV ch. 312 1560 having chosen 2 gaps per HV channel and 6 FEBs per LV channel

I.N.F.N.-CAEN SASY2000 project I.N.F.N. Naples Detector region Control Room 4 8 … 16 HV #1 HV #2 Branch controller #1 Complex ch. 1 256 Remote boards LV #1 LV #4 Branch controller #2 HV #1023 HV #1024 Complex ch. 512 … 256 LV #2047 LV #2048 Branch controller #16 What do we need ?? 26 ch * 12 sect * 5 wheels = 1560 LV 17 ch * 12 sect * 5 wheels = 1020 HV One mainframe is enough for the barrel 48 Volts High Power Source The remote board has 2 Complex ch. each equipped with: 2 HV ch and 4 LV ch.

SASY2000 characteristics Functional Prototypes Remote Rack I.N.F.N. Naples Functional Prototypes Remote Rack SA2001: 2 ch High Voltage Module VOUT = 12 kV IOUT = 1 mA Ripple  200 mV pp SA2002: 2 ch Low Voltage Module VOUT = 4.5  7.5 V IOUT = 1  2 A Ripple  20 mV pp

Magnetic field tolerance up to 5 kGauss Test condition SA2001: VOUT = 8kV, Rload=12 M SA2002: VOUT0 = 4.7 V, VOUT1 = 5.0 V, IOUT0,1 = 1.9A Da 0 a 5 kGauss: loss of efficiency 2% (=Pload/PDC-DC converter) (75%  73%) Future improvements: transformer oriented according  B  it will work reliably up to 8 kGauss

Test performed SASY 2000 prototype I.N.F.N. Naples SASY 2000 prototype The HV-LV prototype 0 consists of: 1 HV board (SA2001), 3 LV boards (SA2002) and 1 controller. It has been split in three pieces, following a “logical separation” of the system, in order to study the functionality of every single piece and component. The following tests has been performed on both the prototypes and will be repeated for the final boards: Magnetic field test up to 7 KGauss (at CERN) (see attached results shown by CAEN @ CERN in May 2002) Radiation test up to 10 LHC eq-years (at Louvain La Neuve) (results shown) Test on the RPC to study the noise condition (to be performed at the test station in Bari); High Stress Test to study the system under very hard conditions (to be performed in Napoli).

Neutron radiation test I.N.F.N. Naples The SASY2000 HV-LV prototype has been tested twice (May-Aug 2002) at the Louvain La Neuve radiation facility. The total neutron fluence requests for 10 LHC years is about 1x1012 n/cm2 (note: in RE1/1 region) corresponding to 2 hours and 40 min with a beam at 1 mA at 70 cm SASY2000 In first session the system worked well for 30 min. corresponding to 1.8 • 1011 n/cm2 (a factor 6 higher than that expected on RB4!) We lost the communication with the prototype. CAEN reported a known loss of current gain due to irradiation on CNY17 opto-insulator used to enable the HV/LV channels. The prototype was irradiated for 80 min corresponding to 4.8*1011 n/cm2. On the second prototype (ATLAS one) the gain current loss was cured using a lower value biasing resistor. Was registered a few SE on the controller with loss of communication but the normal condition was restored after 1 s on power OFF/ON condition (it will be implemented by firmware an HOT RESET to recover the communication without interruption of remote power supply). After the irradiation the SASY2000 was tested outside, preserving its original functionality. (robustness of hardware)

Magnetic field test setup Magnet: MNP24-1 at CERN Bldg. 168 B: up to 10 kGauss B around CMS: .44T Test condition: 0-7 kGauss

Magnetic field tolerance up to 5 kGauss Test condition SA2001: VOUT = 8kV, Rload=12 M SA2002: VOUT0 = 4.7 V, VOUT1 = 5.0 V, IOUT0,1 = 1.9A Da 0 a 5 kGauss: loss of efficiency 2% (// B) 0% ( B) (efficiency defined as =Pload/PDC-DC converter) (75%  73%) Future improvements: transformer oriented according  B  it will work reliably up to 8 kGauss

High Stress Test in Naples I.N.F.N. Naples The High Stress Test is based on a large number of cycles of the following tests: Low current (1 mA) test at “working” voltage (10 KV); Medium range current scan (from 10 to 300 mA) at “working” voltage: High current (1 mA) test at “working” voltage (10 KV); Over-current and Trip test (I > 1 mA); Maximum voltage test (12 KV) at different absorbed currents; Discharge and short circuit test made with two pins at different distances; Imon, Vmon calibration test made with an independent volt-meter. Different HV resistors A PC running LabVIEW will be used to control the system and to analyze the data. Final HV-LV cable/connector will be used.

HV-LV architecture for a barrel sector I.N.F.N. Naples 26 LV channels 4 Remote Boards 17 HV channels RB4 4 LV 2 bi-gaps 2 bi-gaps 4 HV ch 1 RB 2 RB RB3 2 bi-gaps 2 bi-gaps 4 HV ch 4 LV 3 bi-gaps 6 LV ch 3 HV ch RB2 1 RB 1 RB 4 LV ch 2 bi-gaps 2 HV ch 4 LV ch 2 bi-gaps 2 HV ch RB1 1 RB 1 RB 4 LV ch 2 bi-gaps 2 HV ch 2 bigaps = 96 strips = 6 febs LVD channel HV channel LVA channel RB = remote board 26 ch * 12 sect * 5 wheels = 1560 LV 17 ch * 12 sect * 5 wheels = 1020 HV 4 remote boards * 12 sect * 5 wheels = 240 RB

Barrel cables routing LV HV 26 LV ch/cable + 17 HV ch/cable per sector I.N.F.N. Naples 26 LV ch/cable + 17 HV ch/cable per sector LV-HV 1 2 LV-HV LV-HV 3 4 LV-HV Sector -4 Sector -5 LV-HV Muon racks 2 RPC HV-LV crates Sector –6 LV HV 26 LV ch/cable 26 LV 17 HV LV-HV 5 6 LV-HV 7 8 Elect. house 17 HV 26 LV 17 HV ch/cable LV 48 remote boards/wheel  240 Remote Board 1 crates/rack  8 crates/wheel  40 crates 12-Nov-18 26 ch * 12 sect * 5 wheels = 1560 LV 17 ch * 12 sect * 5 wheels = 1020 HV HV