1 / 21

T2 GEM Production in Helsinki

T2 GEM Production in Helsinki. Kari Kurvinen 31.1.2006 TOTEM T2 EDR meeting. Radiation Detector Laboratory of Helsinki Institute of Physics (HIP) and Department of Physical Sciences of University of Helsinki. 28 cm. T2 GEM design. triple GEM foils Ar/CO 2 70/30 gas mixture

pattyr
Download Presentation

T2 GEM Production in Helsinki

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. T2 GEM Production in Helsinki Kari Kurvinen 31.1.2006 TOTEM T2 EDR meeting Radiation Detector Laboratory of Helsinki Institute of Physics (HIP) and Department of Physical Sciences of University of Helsinki.

  2. 28 cm T2 GEM design • triple GEM foils • Ar/CO2 70/30 gas mixture • operating gas gain M = 8000 No bonding anymore HV resistor divider board • design by F.Sauli & L.Ropelewski based on COMPASS GEM design • GEM foils manufactured by CERN • readout boards by CERN and a commercial company Test Cards

  3. READOUT STRUCTURE fully digital readout (no analog information used) 512 strips (pitch of 400 microns) 1560 pads (2x2 -> 7x7 mm2) readout via connectors XXX APV VFAT support rails radial strip readout split asymmetric HV asymmetric spacers

  4. T2 GEM production in Helsinki • construction of 40+ GEM detectors for TOTEM T2 is on responsibility of the Helsinki group. • a ”GEM production line” has been constructed in the detector laboratory of HIP • Compass GEM production as a guideline(ref. M.Capean, B.Ketzer, A.Placci,L.Ropelewski, F.Sauli, M.van Stenis; Construction of GEM Detectors for the Compass Experiment, Technical Note TA1/00-03, CERN-EP/TA1).

  5. Facilities for large GEM production oven for large foils large area probe station ultrasonic bath for large frames dryboxes for leakage current measurements and for storage

  6. Production in clean rooms • almost all the manufacturing phases in clean rooms. • >120 m2 clean room (classes 100 & 1000) available. • usage currently shared by TOTEM and ALICE groups.

  7. Clean room monitoringParticles • temperature and humidity is continuously recorded as well

  8. Main tasks in the production • cleaning and varnishing of the frames. • glueing of the drift electrode. • streching and glueing of the GEM foils. • testing the readout boards. • assembling all the parts together. • assembling connectors (gas, HV). • checking gas tightness. • electronic tests. • Handling procedures of the separate detector components are registered into a database.

  9. A lot of manual work!

  10. GEM FOILS • visual inspection (coordinates of the major defects recorded). • optical scanning • dried in a desiccator. • 1. leakage current measurements of all the segments in the foils (criteria <0.5 nA). • streching and glueing on the frames • curing > 16 hours in oven • cut out from the foil • 2. leakage current measurements

  11. Leakage current measurements of GEM foils • the four segments of the GEM foils are measured separately by a picoamp meter. • leakage currents measured three times during assembly (as a bare foil, after framing and after gluing into a stack). 36 measurement / detector • a foil approved if current stays < 0.5 nA for 30+ min @500V HV ramp up spark! in N2 > 5 min in N2 C-segment B-segment 12 min 12 min Present status: 21 foils checked (incl. prototypes), 2 failed

  12. READOUT BOARD • visual inspection • capacitance measurement • probe station & LCR meter • semiautomatic relay system • connectors soldered • short circuits burned

  13. Assemblingcomponents together • in clean room of class 100 • all the three framed GEM foils are glued one after the other on the drift frame (a special press constructed). • consumption of the glue measured. • 3. leakage current of the GEM foils checked after gluing. • GEM stack glued on the readout board.

  14. Assembling connectors gas tightness by Araldite & Dow Corning 1-2577 assembling: • the voltage divider PCB • the adapters for the gas connectors and blocking the holes on the backside. • HV cables

  15. TESTS • GAS LEAKAGE TEST • ELECTRONIC TESTS • HV test in CO2 or N2 • Basic measurement (gas amplification, energy resolution) • Stability measurement • Gas gain scan over active area.

  16. Gas tightness TOOLS AVAILABLE • comparison of in- and outflow • leak detector • oxygen measurement from the outflow

  17. Basic measurementsof HG1 55Fe

  18. Gas gain scan of readout sectors The gas gain of the whole readout sectors (128 strips or 120 pads) are measured. Due to different capacitances of pad and strip sectors and a limitation of preamplifier used the measurement may not be compared between pad and strip sectors.

  19. Gas gain scan with a point source • Different areas of the second half of the HG1 GEM were irradiated by 55Fe source (50 points) • 128 strips or 120 pads readout Std.dev.: on inner strips 5.8% on outer strips 10% on pads 8.1%

  20. STATUS Jan. 2006 Prototypes T2 GEMs • two built in Helsinki during 2005 • chambers for 3rd,4th and 5th GEMs finished one for the beam test (Nov. 2004) two built in Helsinki during 2005

  21. Conclusions • the radiation detector laboratory of Helsinki has unique facilities to assemble and test large area gaseous detectors. • a production of TOTEM T2 GEMs has successfully started.

More Related