WG1 summary P. Colas, S. Duarte Pinto RD51 Collaboration meeting in Bari October 7-10, 2010.
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Transcript of WG1 summary P. Colas, S. Duarte Pinto RD51 Collaboration meeting in Bari October 7-10, 2010.
WG1 summary
P. Colas, S. Duarte Pinto
RD51 Collaboration meeting in Bari October 7-10, 2010
Outline• Large area MPGDs (task 1)
– GEMs for CMS– Micromegas for ATLAS
• New structures (task 2)– Thin-mesh and segmented Micromegas– Laser-etched meshes– Light and ionisation– THGEM RICH– Neutron detection
• HV (task 4)
10/10/2010 2RD51 Bari WG1
Micromegas DHCAL first m²• Fine segmentation 1cm²,
thickness 8mm for ILC hadronic calorimetry
• HardROC 2 chip too fast shaping -> calibration and threshold setting critical
• 1m² assembled• Tested in 1kHz beam• Future microROC much better
suited (low noise, longer shaping)
• Hope to use the RD51 telescope
10/10/2010 RD51 Bari WG1 3
GEM for CMS muon chambers
• Trapezoidal detector in the forward region• GE1/1 prototype : 1 m x 45(22) cm, 19 mm thick, 35 HV
sectors of 100cm², 4.5 kV operating voltage. HV divider• Largest size single-mask GEMs. (Rui’s workshop)• Collaboration with Florida IT : thermal stretching by infrared
heating. • RD51 beam test starting October 18.
10/10/2010 RD51 Bari WG1 4
Micromegas for ATLAS muon chamber
• Was presented in WG2 (see WG2 report)• CSC-like chamber being built• Beam test in H6 at the same time as RD51• Saclay telescope optimized and ready to study
sparks
10/10/2010 RD51 Bari WG1 5
[email protected] 6RD51 Collaboration Meeting, Bari October 8th, 2010
Current and voltage behaviour at 10 KHz/cm²Current and voltage behaviour at 10 KHz/cm²Current and voltage behaviour at 10 KHz/cm²Current and voltage behaviour at 10 KHz/cm²
Standard bulk (SLHC2: 2mm)
Resistive strip bulk (R6: 1mm, 400kΩ/)
SLHC2: HV=400V (Gain ~3000): - current when sparking < 0.4 mA -voltage drop< 5%R6: HV=390V (Gain ~3000): - current when sparking < 0.08 mA -voltage drop<0.5%
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Mesh VoltageMesh Current
Ar /CF4/Iso (95/3/2)
Double-sided, thin and segmented meshes at Saclay bulk workshop
• Very inventive detectors being tried. • Double-sided : coarse readout on
one side, finer multiplexed readout on the other side
• Bulk with thin meshes• Also trying thick meshes (90%
cheaper)• The Saclay bulk workshop is now
ready to help
10/10/2010 RD51 Bari WG1 7
PCB top side36 x36 strips with a pitch of 200 µm
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Multiplexed strips: 36 x 36 = 1296
-Stephan AUNE- RD51 BARI. Saclay MPGD workshop R&D09/10/2010 8
i r f u
yalcas
i r f u
yalcas
Clas12 double sided bulk for cosmic bench
Microbulk, light and ionisation
10/10/2010 RD51 Bari WG1 9
• Recent improvements : low radiactivity, removing kapton gives better gain and resolution, 25 µm gap now exists. Used in CAST.
• Scintillation at high pressure. Maximum gain (both scintillation and ionization gains remain reasonable at high pressure)
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ain
Pressure (bar)
MM-charge MM-scint S-THGEM S-GEM 3-GEM MHSP
Ultrafast laser drilling
10/10/2010 RD51 Bari WG1 10
• New high-rate ‘fs’ lasers make it possible to drill more perfect holes (no melting) in quantities.
• Might replace wet etching for some materials (ceramics) or down to 10 µ diameter
fs ps ns µs
Various processes at various time scales
Laser trepanned hole
Data taken in He + 20% isobutane at 375 V
10/10/2010 11RD51 Bari WG1
HARPO : polarimetry in the few-MeV region for astrophysics
10/10/2010 RD51 Bari WG1 12
• Use the triplet interaction e- -> e-(soft)e+e-• 5 bar TPC, (30 cm)3 with 2D strip (1mm) readout• 3 phases: demo at ground, balloon flight, satellite
THGEMs for RICH
10/10/2010 RD51 Bari WG1 13
150 GeV µ. Detect Cerenkov light from a quartz radiator.3-GEMs with CsI photocathode
Circle : expected from CerenkovBlue : overlap of events
Neutron detection with GEMs at Beijing
10/10/2010 RD51 Bari WG1 14
• GEM with Boron converter• Scanning with a 239 Pu source
Small and new-type High Voltage supply
• Cockroft-Walton chain• 25 units being produced at
Nikhef• Accurate current monitoring• Can provide divided HV to
several GEMs• Suitable for a large TPC? Could
be integrated to the cage?
10/10/2010 RD51 Bari WG1 15