Presentation on theme: "RD51 10-2008. S. Aune CEA/IRFU Micromegas Bulk for CLAS12 vertex tracker."— Presentation transcript:
RD51 10-2008. S. Aune CEA/IRFU Micromegas Bulk for CLAS12 vertex tracker
RD51 10-2008. S. Aune CEA/IRFU Micromegas for CLAS12 Micromegas (MM) as central tracker for the CLAS12 experience at Jlab in 2014 CAD Study and remote electronic Curved Bulk prototyping and tests – Saclay bulk test 2007 – CERN Prototyping and tests in Saclay 2008 MGPD in 5T field –Lorentz angle study and test First curved: Saclay 2005
RD51 10-2008. S. Aune CEA/IRFU Vertex tracker why Gaseous, compared to Si ? Less material (~.0015 L R ) Larger ΔR → same intrinsic momentum and angle resolution for less channels smaller dead zones Cheaper Resistant: “immortal while breathing”
RD51 10-2008. S. Aune CEA/IRFU Mixed solution: Silicium + Micromegas bulk Central detector –2 planes of Silicium (X,Y) –3 cylindrical bulks (XY): 3m 2, pitch 0.6 mm,10k channels. Forward detector –4 plane bulks (XY): 1 m 2, 3k channels. 600 mm for 500 mm FVT Silicium target Cylindrical bulks beam Bulk tracker Project for CLAS12 at Jlab
RD51 10-2008. S. Aune CEA/IRFU Mechanical & electronic implantation ? Conclusion: Mechanical implantation possible Curved detector for “Y strip” Electronic needs to be remote “As Far As Possible” (compass: 300 mm) –Test done on long kapton braid Study of a ad hoc ASIC for tracker to be decide A CAD study was done with curved detectors. 3 double, X and Y strips at 90°, cylinders around the target with a 3 double end cap.
RD51 10-2008. S. Aune CEA/IRFU 3D remote-elec. model Good solution to be validated with long (> 800 mm) electronics braids
RD51 10-2008. S. Aune CEA/IRFU Saclay Bulk Lab (2007) PCB used: FR4 from 60 to 200 micron Kapton 25 to 100 micron mesh used: Woven wire 19 micron The thin PCB is transformed in bulk flat and then curved. The Detector are made in a bulk lab using PCB machines design for university. The ability to realize the bulk allowed fast R&D with several configuration
RD51 10-2008. S. Aune CEA/IRFU PCB: 100 µm FR4 with 5 µm thick Cu strip 100 µm amplification gap Woven Mesh Gantois non stretched bulk with an array of 400 µm pillar every 2 mm Dimension: 180 mm x 60 mm First curved bulk (09-2006) Picture: bulk curved, 100 mm radius
RD51 10-2008. S. Aune CEA/IRFU First prototype test 15 proto realize, 14 tested E/E ~ 40% vs 25% on thick bulk 1 er Fe 55 pick on a curved bulk Study for drift pillar
RD51 10-2008. S. Aune CEA/IRFU Thin bulk micromegas Prototype made at CERN (2008) Thin bulk (15 x 10-4 LR), long (600 mm) detector with a remote (800 mm) ASIC (AFTER)
RD51 10-2008. S. Aune CEA/IRFU PLV1 curved tests One prototype was curved on a Y structure. We obtained a good gain homogeneity and E resolution degrade to 40%. Before drift integration Under test Drift integration
RD51 10-2008. S. Aune CEA/IRFU Curved bulk integration
RD51 10-2008. S. Aune CEA/IRFU Curved bulk integration Issue to be solved –Temperature curing during bulk fabrication process: differential thermal dilatation on thin PCB –Tension on the mesh vs. curvature Sealed drift –A 100 µm aluminize mylar is silicon glued with a 2 mm thick silicon join on the PCB. Gaz capillary tube glued either on drift or on PCB
RD51 10-2008. S. Aune CEA/IRFU Gain on curved bulk First test under way, similar gain behavior with small increases depending of curvature.
RD51 10-2008. S. Aune CEA/IRFU Before curvature energy calibration Energy resolution
RD51 10-2008. S. Aune CEA/IRFU Energy resolution degraded due to in-homogeneity in the amplification gap. 38.8 % FWHM versus 20% flat Possible solution: Nylon/metal mesh Curved process pcb mesh Curved bulk energy resolution
RD51 10-2008. S. Aune CEA/IRFU Flexible cable measurement Different flex PCB cable were realise at CIRE/SPCI: Strip cables (40cm, 80cm et 80cm U-shaped) Wire cables (40 cm, 80cm et 80 cm U-shaped) Noise and crosstalk measurement test were conclusive for 800 mm. Flex PCB cable, 80 cm U-shaped Acquisition made with T2K Labview DAQ Software
RD51 10-2008. S. Aune CEA/IRFU AFTER signal on the strips Signal Time (x 50 ns) ADC 55 Fe shaped signal Signal - noise Noise Channel 71 512 time samples
RD51 10-2008. S. Aune CEA/IRFU Noise study: preliminary results Pedestal for channel 71
RD51 10-2008. S. Aune CEA/IRFU Magnetic environment to deal with : 5 T orthogonal to the detector ! e-e- tanθ = v x B / E Standard conditions : E= 1 kV/cm, v= 8 cm/μsec θ = 75 ° Adapted conditions: E= 10 kV/cm, v= 5 cm/μsec θ = 14° Gaseous detector in 5T field ?
RD51 10-2008. S. Aune CEA/IRFU Lorentz angle behaviour with the magnetic field Lorentz angle mesured from the deviation of the B=0T peak Drift distance: 2.25mm The signal spreads out with the Lorentz deviation → increase the resolution B = 0T B = 1.5T Labview DAQ
RD51 10-2008. S. Aune CEA/IRFU Lorentz angle behaviour with the drift HV
RD51 10-2008. S. Aune CEA/IRFU Out In 400 mm Test at 5T Test done at Jlab on the DVCS magnet. The prototype is fixed on a mobile cart (telescopic slide rail) itself fixed on the magnet. The handcart allows full test in and out without dismounting the detector. Will be used for future test @ 5T with DVCS magnet.
RD51 10-2008. S. Aune CEA/IRFU Y cylinder X tile Y connector Y HT cable Y joint Interface attachment to handcart Length: 600 mm Diameter: 180 / 220 mm 1728 Channels Magnet interface (3 Teflon pads) Cylindrical prototype Curved bulk demonstrator