1 / 23

Construction & Commissioning of Full-size GEM prototypes for the CMS High-  Muon System

Construction & Commissioning of Full-size GEM prototypes for the CMS High-  Muon System. Marcus Hohlmann (Florida Institute of Technology) with C. Armaingaud, S. Colafranceschi, R. De Oliveira, and A. Sharma (CERN) on behalf of the CMS GEM Collaboration.

arich
Download Presentation

Construction & Commissioning of Full-size GEM prototypes for the CMS High-  Muon System

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Construction & Commissioning of Full-size GEM prototypes for the CMS High- Muon System Marcus Hohlmann (Florida Institute of Technology) with C. Armaingaud, S. Colafranceschi, R. De Oliveira, and A. Sharma (CERN) on behalf of the CMS GEM Collaboration 2012 IEEE Nuclear Science Symposium, Anaheim, CA N38-6 Nov 1, 2012

  2. MOTIVATION & INTRODUCTION

  3. Premise for CMS GEM upgrade • CMS was designed with a “hermetic and redundant muon system” – Joe Incandela, CERN “Higgs Discovery” Event, 7/4/12 • But: CMS currently has the least redundancy in the most challenging muon region, i.e. at |η| > 1.6: • RPCs descoped; only Cathode Strip Chambers currently present • Long-term functioning of the muon system into LHC Phase II (beyond Long LHC Shutdown 3) is of vital interest for CMS. Use Phase I to evaluate muon technology for Phase II. • The high-ηmuon region in particular will need robust and redundant tracking and triggering at the anticipated higher muon rates • Additional muon detectors with high spatial and temporal • resolution in the high-η endcap region could bring benefits • in triggering, reconstruction, and ID for muons: → GEMs

  4. CMS GEM Endcap Chambers The currently un-instrumented high- RPC region of the muon endcaps presents an opportunity for instrumentation with a detector technology that could sustain the radiation environment long-termand be suitable for operation at the LHC and its future upgrades into Phase II: GEM Detectors GE1/1in YE1 nose GE3/1 GE4/1 GE2/1 on back of YE1 CMS Detector

  5. Method of Integration into CMS Installation sequence: Four superchambers in their final position Superchamber (Two Triple-GEMs) Mounting on yoke disk A. Conde Garcia

  6. Expected Benefits for Reconstruction & Trigger Expected gains in momentum resolution at high-pT Staving off looming muon trigger inefficiencies at high- Simulation Expected CSC inefficiency at PU=400due to Cathode LCT - Anode LCT timing mismatching for one GEM station A. Safonov (Texas A&M) Acceptance impact:  distribution of 4 muons in H → ZZ → 4µ 1.6<<2.4 M. Maggi (Bari) – GEM Workshop 3 Strip Readout granularity: # GEM strips / # RPC strips (orig. TDR) Paolo Giacomelli (Bologna) & Markus Klute (MIT) – GEM Workshop 3

  7. CONSTRUCTION OF FULL-SIZE GEM PROTOTYPES

  8. Evolution - GEM foil stretching Current state-of-the-art: Self-stretching assembly without spacers (CERN) Readout PCB Tightening the horizontal screws tensions the GEMs & seals gas volume GEMs Drift electrode Detector base pcb only glue joint in assembly Allows re-opening of assembled detector for repairs if needed. 2012 R. De Oliveira, CMS-GEM/RD51Workshops CERN & U. Gent

  9. 3rd CMS GE1/1 Prototype: “Self-Stretched - Sans Spacer” No spacers in active volume GEM foil with inner & outer frame GEM foil in inner frame assembly GEM tensioning base pcb with drift electrode Vias for strips sealed w/ kapton compact HV divider -sector with 384 radial readout strips (12.4 cm long) HV noise filters Chamber closed by readout board with Panasonic connectors for frontend electronics 2012 Inside of readout board with O-ring seal

  10. CMS Full-size GE1/1 Detector Prototype • GEM active areas: 990 mm  (220-445) mm • Single-mask technology • 1D radial strip read-out with 3 8 128 = 3,072 channels • HV sectors: 35 • 3/1/2/1 mm gap sizes • Gas mixtures: • Ar/CO2 (70:30; 90:10) • Ar/CO2/CF4 (45:15:40; 60:20:20) • Gas flow: ≈ 5 l/h The new self-stretching technique has been applied to the full-size CMS GEMs Production of 5 prototypes launched in May 2012

  11. Prototype Production: Status & Plans 4 chambers completed at CERN • 2 in SPS test beam in summer; 3rd being prepared for fall TB • Some issue with dust particles from fiberglass frame getting into active GEM area in first two prototypes • micro sand blasting & polyurethane coating of frames → change to different material (PEEK) for inner frame that holds GEMs • 1st chamber to be assembled and commissioned outside CERN this fall (at Florida Tech) After sand blast Frame after machining After PU coating

  12. Next Prototype: No Gluing & PEEK frames Panasonic readout connector Readout PCB On-foil protection resistors Outer frame GEM foils Use O-ring to seal outer frames to drift plane Inner frame Drift Board As a lot of dust was released during the screw insertions into FR4 frames, CERN has replaced FR4 by PEEK for inner frames. PEEK is one of the best polymers in terms of: -radiation tolerance -mechanical properties -outgassing -chemical resistance Rui De Oliveira

  13. Summary of GEM production & Plans • We are now below 2 hours for the GE1/1 assembly • with the self-stretching technique • (after gluing outer frames to drift) • Three 30cm  30cm detectors have been produced • Up to now  ok • Four 1.2m  0.45m detectors have been produced • 2 tested OK  but gain uniformity still to be improved • 2 others currently being tested • Four new ones will be produced with all the improvements • to reach final specifications (< 30% gain non-uniformity) • Preparing a new laboratory for CMS GEM assembly and • quality control at CERN (spring 2013) Rui De Oliveira

  14. COMMISSIONING OF FULL-SIZE GEM PROTOTYPES

  15. CMS GEM Summer Test Beam Effort at SPS See Poster N14-137

  16. 3rd GE1/1 Prototype: Commissioning Results Fe55 spectrum Preliminary Preliminary 2012 test results (bench tests & beam test at SPS H4) Rate plateau Gain uniformity

  17. Long-term Aging Test at CERN GIF CMS prototype Motivations • Ensure long-term operation in CMS • Understand the effects of the radiation on the materials • Understand aging origin (if any) and propose solutions lead shield CMS high-η maximum integrated charge Gain of 2x104 50 MHz/cm2 X-rays, 10 days = > 20 C/cm2 integrated (LHCb) GEM settings: Drift: 3kV/cm, Others: 3,5 kV/cm Induction: 5 kV/cm Gain: 8 x 103 – 104 Gas Mix: Ar/CO2/CF4 (45:15:40) See Poster N14-138 The CMS full-size prototype has been installed in the CERN Gamma Irradiation Facility over the summer The detector performance is being monitored along with environmental/gas variables Armaingnaud/Merlin/Rohee/Furic/Buhours

  18. Continuing R&D: Zigzag strips to reduce readout channel count while maintaining high spatial resolution Beam Test 2012 Zigzag Resolution: /2 = 73 µm With 2mm strip pitch Preliminary Results CAD Design by C. Pancake, Stony Brook 2 mm 2 mm

  19. PLANS FOR INSTALLATION IN CMS

  20. GEM Installation in LHC Long Shutdown 1 CMS P5 CAVERN UXC Integration and Installation of 2 GE1/1 superchambers = 4 GE1/1 chambers (and possibly 1 super-chamber GE2/1) Measure in situ: • Rates, Background/Noise, Stability, Uniformity, Efficiency • Spatial resolution • In the actual high-η environment • In actual magnetic field ME2/1 GE2/1 Participate in CRAFT 2014 Proposed to CMS Upgrade Management YOKE ME1/1 4 GEM chambers in LS1 • Split signal to CSC and participate in CMS muon trigger and reconstruction • Install new pre-production TMB prototypes on chambers that overlap with GEMs • Prove that the electronics design is working and demonstrate in situ that we can operate CSC TMB with GEM input in various operating regimes • Reduce CSC X-Y ambiguity and ghosts • Once we go into beam operations, we will demonstrate the above again, this time measuring muon trigger rates and efficiency with and without GEMs. GE1/1 GE1/1 ME1/1

  21. GEM DAQ Prototype System for LS1 DAQ also with link to new CSC Trigger Mother Board Gigabit Link Interface Boards P. Aspell

  22. Summary & Outlook Long Shutdown 1 (LS1) • 4 full-size GE1/1 detectors successfully constructed using simplified self-stretch & sans spacer technique; being validated • GEM electronics and DAQ prototype underway • Installation, services, and integration with CSC’s underway • Zero additional cost to CMS upgrade projects • GEMs to participate in CRAFT 2014 Long Shutdown 2 (LS2) • A GE1/1 station can be completed and installed in LS2 • Capacity in CERN Workshop to produce all (72 validated) detectors in 2 years; final electronics ready for 2015 • Cost 2-3 MCHF

  23. Thank you for your time! We would like to explicitly acknowledge here the strong technical support received from the RD51 Collaborationfor this project!

More Related