Muon EDR: Chamber design M2/3 R1/2 16/04/20031T.Schneider/LHCb Muon EDR 1.General description - AW read out -Cathode pad read out -HV supply 2.Details about the PCBs for the pad read out 3.Details about the AW bars 4.Special solutions different to the other designs -Chamber closing (O-Ring + 2.5mm spacer) -HV interface 5. Remaining open issues before mass production -Component choice for capacitors and resistors =>components inside or outside the gas volume -Single/double cathode read out -Test foam panel production for inner regions 6. Time schedule

Muon EDR: Chamber design M2/3 R1/2 16/04/20032T.Schneider/LHCb Muon EDR 1. General description: - 5 panel sandwich construction -4 gas gaps of 5mm each -Combined anode wire/ cathode pad read out

Muon EDR: Chamber design M2/3 R1/2 16/04/20033T.Schneider/LHCb Muon EDR 1. General description: -Wire read out on top -Cathode read out on the sides -HV bus on the bottom

Muon EDR: Chamber design M2/3 R1/2 16/04/20034T.Schneider/LHCb Muon EDR 1. General description: AW read out Signal (black connector) is brought via the Anode wire bars to the HV cards Detector ground (white connectors) is picked up from the opposite cathode planes

Muon EDR: Chamber design M2/3 R1/2 16/04/20035T.Schneider/LHCb Muon EDR 1. General description: Cathode pad read out: Signal and ground (grid of cathode pad structure) is going to the spark protection board (SPB) Additional ground from the other 4 cathodes is connected via soldered copper strips (CMS/EMU solution)

Muon EDR: Chamber design M2/3 R1/2 16/04/20036T.Schneider/LHCb Muon EDR 1. General description HV Supply: HV bus included on the anode wire bar Loading resistors soldered on the out sticking part of the anode wire bar

Muon EDR: Chamber design M2/3 R1/2 16/04/20037T.Schneider/LHCb Muon EDR 2.Details about the PCBs for the pad read out (quarter of PCB) Double sided PCB with 1.6mm thickness 8*8 pad structure (top) Ground grid with ring around (top) Read out traces separated with ground traces (bottom)

Muon EDR: Chamber design M2/3 R1/2 16/04/20038T.Schneider/LHCb Muon EDR 3. Details about the AW bars Kapton layer glued with epoxy on the anode wire bars in PCB production to protect and isolate the HV traces. Smoothes the steps of the HV traces to avoid micro leaks where the O-ring crosses.

Muon EDR: Chamber design M2/3 R1/2 16/04/20039T.Schneider/LHCb Muon EDR 4. Special solutions different to the other designs Chamber closing: O-ring +2.5mm spacer To close and seal the chambers for the inner part of the Muon system a standard Ø 3mm O-ring is used. This solution allows us to test the chambers in the final conditions. In case of problems we can at any time intervene and correct the error with little effort.

Muon EDR: Chamber design M2/3 R1/2 16/04/200310T.Schneider/LHCb Muon EDR 4. Special solutions different to the other designs Chamber closing: O-ring +2.5mm spacer

Muon EDR: Chamber design M2/3 R1/2 16/04/200311T.Schneider/LHCb Muon EDR 4. Special solutions different to the other designs Chamber closing: O-ring +2.5mm spacer Precise bar gluing (2.5mm) and 2.5mm brass spacers guarantee the 5mm gap size Screws close the chamber at the spacer place. A controlled torque of 1Nm is applied to the M5 screws with a dynamometric screwdriver.

Muon EDR: Chamber design M2/3 R1/2 16/04/200312T.Schneider/LHCb Muon EDR 4. Special solutions different to the other designs HV interface: - Because of high density of capacitors special solutions are required: In present design standard components are mounted on external PCB’s -Open HV lines are covered with special varnish -Ground is brought on the side to the PCB (3 pins)

Muon EDR: Chamber design M2/3 R1/2 16/04/200313T.Schneider/LHCb Muon EDR 5. Remaining open issues before mass production Alternative solution for HV interface: The use of SMD components would allow us to mount them on the chamber /in the gas volume. Advantages: -no HV cards/connectors -HV components in the gas volume not exposed to external humidity changes =>better dark current behavior

Muon EDR: Chamber design M2/3 R1/2 16/04/200314T.Schneider/LHCb Muon EDR 5. Remaining open issues before mass production Single/double cathode read out:pad wire plane  wire plane full groundpad Advantage of double cathode read out is the double signal pulse height on the pads For cathode readout only: =>Tested successfully on M1R1 prototype. For combined readout: =>Will be tested in the June test beam

Muon EDR: Chamber design M2/3 R1/2 16/04/200315T.Schneider/LHCb Muon EDR 6. Time schedule June test beam: Single/double sided cathode read out test on combined read our Proto-type (M2R2) July: Aging test in Casaccia (test of SMD components inside the gas volume) August test beam: Module 0 M3R1 (foam panels) test September: PRR for CERN production site