Minutes of the forward endcap EMC meeting, 11th of April 2015, SeeVogh, 14:00-16:00

• Basel: Werner, Natalie
• Bochum: Cathrina, Claudius, Fritz-Herbert, Malte, Mario, Matthias, Miriam, Patrick, Stefan, Tom, Tobias H., Tobias T.
• Bonn: Christoph, Matthias, Ulrike
• Groningen: Excused
• Uppsala: Pawel (partly)
• GSI: -

• Gain for VPTT preamplifier
  • Christoph, Matthias: From measurements with cosmics, channels 12/9: 186 mV/MeV, 145 mV/MeV.
  • Malte: to be compared to Bonn test beam result of about 145 mV/MeV.
  • Conclusion: Measure two more channels (3 days).
• Tom: VPTT preamps with modified gain work at -25 degrees.
• Voltage divider can be produces (parts are ordered)
• Werner: Parts for VPTT preamp tests arrived, will send next week VPTT and APD preamps with modified gains/parts to Bochum.

• Christoph: HV cable with 3.2mm diameter for PANDA to services hut possible. 5 kV, CERN specs. 20 m sample available. SHV connector can be used. Question SHV on both sides?
• HV Patch panel: H&S with Molex to SHV?
• HV cable for APDs in aleveole: irradiated and tested at 80 degrees. ok for 1 kV (Christoph).
• Alveole PCB
  • 8pin connectors for sensor cables: Need to glue! Werner: version with latches possible?
  • LV distribution open.

• Christoph: Can start production of 16er interface pcs. (45 min per pc.)
• Should be produced according to drawing with mounting holes on one side and air cooling holes on other side.
• Malte: Need to modify manipulation prototype. Will put drawings in EDMS.
• Mounting holes need to be defined for 8er interface pieces!
• Crate design: Will be discussed in special meeting on Monday, May 18.

• Pawel: One board with special input filters. Works, now at KVI. Production of 5 remaining boards on hold. Need to define input filter (neutral filter).
• Pawel: KVI should send ADC board back to Uppsala to work on input filter.
• For forward endcap EMC need input filter with 50 Ohm input single ended and splitting to high/low gain channel.
• Pawel: Depending on opt. transceiver 5mm shrinking maybe possible.
• Christoph will send Pawel drawing of shaper test board. Pawel will send to Bonn/Bochum information which resistors should be changed to adapt for new filter, single ended input and 50 Ohm termination while keeping high/low gain split.
• Matthias: Can splitting high/low gain be done on the ADC, not in the backplane? Needs less connectors, less reflections.

• Ulrike: Status of APDs?
  • Tobias: Reproduceability of QE measurements at per mille level (from excel sheets from Andrea)
  • Fritz-Herbert: Irradiation of APDs in Giessen on hold. Waiting for data on QE measurements.