Status of a medium resistivity prototype in Ferrara 01/29/2003
History
- December
-- After about 20 days of conditioning, Profile 1 was able to reach the voltage of 4900 V.
-- The tube has been turned off during Christmas Holiday (about 15 days) with no gas.
- 4 January
-- The has been turned on with a gas mixture without Ar for about 15 days (C4H10/CO2, Ar was finished).
- 23 January
-- Now we are using ternary gas mixture.
-- Conditioning of Profile 1 and 2 for about 5 days, but no good behaviour.
- 28 January
-- The tubes draw about 2 uA at 4400 V and we are not able to reach voltage above this value.
-- We open the tube and here there are some pictures which show bad conditions.
Bad coating of graphite (profile 1)
Something like black dust on the graphite below the wire (profile 1)
Black dust in the profile 2
