EMU CMS Meeting

1. EMU CMS Meeting Summary of the CSC aging tests O.Prokofiev Fermilab Copy of slides prepared for EMU meeting in 2002

2. Aging Tests Aging tests 1997 - 2001 Results SEM/XEM measurements Closed loop gas system operation and air infiltration rate

3. Soldering Epoxy RTV Epoxy Gluing Soldering Epoxy RTV O-Ring Chamber Materials, Components and Chemicals Chamber material: Panels - FR-4 sheets + polycarbonate core Gap bars, anode bars, spacers - FR-4 Anode wires - LUMA gold plated tungsten Guard wires - gold plated CU-Be guard Components: Capacitors - ceramic, 1nF, 7.5 kV Resistors - carbon composite O-Ring – rubber fluorocarbon Chemicals: Epoxy - 2216, part A and B (constructional epoxy) Epoxy – Epolite 5313 + hardener (wire gluing) RTV - 41 + curing agent (outside chamber sealing) Solder wire Almit KR-19 SH RMA , Seika Corp. (new product)

4. Aging Test at CERN (2000-2001) • Full Scale CMS ME1/2 and ME4/1 chambers from production line • Large (2/3) chamber area irradiated, accumulated dose > 30 LHC years • Two rounds of ageing tests: • premixed gas, open loop gas system, • 1 volume/day (GIF-2000) • closed loop gas system, 4 volume/day, • 5% refresh gas (GIF-2001)

5. EMU Closed Loop Gas System Prototype Closed Loop Gas System Prototype for Aging Tests at CERN Gas System Prototype was constructed at CERN in March 2001 by F.Hahn group

6. EMU Closed Loop Gas System Prototype Goal: - Investigation of CSC operation with Closed Loop Gas System Prototype - Gas mixture monitoring - Chromatographic analysis to measure Impurities level - air infiltration rate measurements (O2, N2, H2O)

7. EMU Gas System Specification Basic Specification

8. EMU Gas System Prototype GIF - 2001

9. EMU Gas System PrototypeGas purity, Flow rate

10. ME1/2 Chamber Oxygen contamination ME1/2 Chamber: At nominal flow rate 12 l/hour oxygen level is ~ 150 ppm

11. ME4/1Chamber Oxygen Contamination 100 600 Oxygen sensor kaput 500 Oxygen vs Flow 80 Oxygen 400 Flow Rate 60 Flow rate, l/hour Oxygen, ppm 300 40 200 Gas system operation without chamber 20 100 0 0 0.0 200.0 400.0 600.0 800.0 1000.0 1200.0 1400.0 Time, hour (from 6.10.01) ME4/1 Chamber At nominal flow rate 12 l/hour oxygen level is ~ 200 ppm

12. EMU Gas System Prototype Oxygen Level Estimation ~ 16 ppm Oxygen Contamination Gas System + Chamber: Nominal Flow Rate - 12 l/hour ME1/2  150 ppm ME4/1  200 ppm Gas System : Flow Rate 12 l/hour Oxygen  16 ppm (2 measurements) ME4/1 Chamber

13. Small chambers (ME234/1, ME1/23, Volume ~ 100 l ) Data: Flow Rate = 12 l/hour, O2 = 150 - 200ppm Oxygen intake is about ~ 2.0 - 2.5 cm3/hour/chamber Chamber Leak Limits: 60 - 120 cm3/hour (1 - 2 cm3/min) Large chambers (ME234/2, Volume ~ 200 l ) No data. It should be twice more than for small chambers Oxygen intake is about ~ 4.0 – 5.0 cm3/hour/chamber EMU Gas System Distribution: 3 ME234/2 or 3 ME234/1 or 4 ME1/23 per gas channel Flow rate / gas channel = ~ 50 l/hour Oxygen estimation at nominal flow rate ~ 50 l/hour: Large chambers (3/ch) : O2 ~ 15 cm3/h/ch 300 ppm Small chambers (3-4/ch) : O2 ~ 7.5 cm3/h/ch 150 ppm Technical specs on Qxygen limits: 100 ppm Need to change to 500 - 1000 ppm ??? EMU Gas System Oxygen Intake Estimation

14. EMU Gas SystemNitrogen Intake Estimation EMU Gas System parameters: Detector volume ~ 66 m3 Nominal gas flow rate ~ 7.0 m3 / hour Number of gas channels - 81 Fresh gas injection – 5%(350 l/hour) from nominal flow rate Renewing gas mixture in the system ~ 8 days (~200 hours) Nitrogen Estimation GIF-2001: - fresh gas injection ~ 0.6 l/hour - O2 ~ 2.0 - 2.5 cm3/hour N2~10 cm3/hour - N2level~1.7% (17000 ppm) ??? EMU gas system Oxygen intake is ~ 7.5 – 15 cm3/hour/gas channel Nitrogen should be 4 times more than Oxygen that is ~ 50 cm3/hour/channel or 8.0 l/hour for all detector (162 channels) Nitrogen level in the system will be ~ 1% or 10000 ppm??? Nitrogen limit (technical specs) is 3000 ppm

15. EMU Gas SystemGas Mixture Impurities Limits Need to make more measurements on oxygen and water contamination in the CSC chambers