Transcript Slide 1 - LHCb Muon

Wire pad chambers
5 V x 50 ns
2 V x 500 ns
Discharge seen at the 8.2 ohm resistor short-circuiting
legs of the capacitor. A.U. (approx 20 V)
This spark is known to be fatal for the 8k20 resistor
(less fatal for 8R2).
We do not observe (with same probe sensitivity) signals
in the same point when the chamber is discharging
inside the wire pad connected to that resistor.
Just for test we generate discharge inside the chamber
(between the soldering pads on the HV bar)
keeping one wire pad to 2 kV and the neighbour to 0 V
Same A.U as before, approx 8 V (but x 10 time scale)
The instantaneous energy release should be largely
smaller
Cathode pad chambers
100 mV x 1 us
50 mV x 50 ms
Discharge seen at the 8.2 ohm (on the cathode pad)
resistor short-circuiting the legs of the capacitor. Same
probe as before (approx 500 mV)
We do not observe (with same probe sensitivity) signals
in the same point when chamber is discharging inside
the wire pad connected to that resistor.
We also generated discharges inside the chamber. Here
we see trains of discharges with very long time scale
(pickup again from the cathode pad) Same A.U as before
(approx 100 mV)
None of these discharges appear fatal for the resistors.