A (B. B.): All elements in the chamber (except the wires) were cleaned with isopropyl alcohol. The Al endplates (from DIXI, Le Locle, CH) and the Beryllium beam pipe (from ELECTROFUSION, Fremot, CA, USA) have not received any surface treatment. We used wires from LUMAMETAL, Sweden. The TEC was wired and assembled in a CLASS 1000 clean room and all manpower inside had to comply with the rules for this CLASS.

A (B. B.): The mixture was, as I said, 80% C0₂ and 20% iso-C₄H₁₀. We have used C0₂ 4.8, i.e. purity of 99.998%, and isobutane 3.5, i.e purity 99.95%. The test chamber as well as the data did not indicate any change of the drift velocity after a new gas refill.

A (B. B.): The chamber has still not been opened after dismantling. But I have said there was no degradation of the anode pulse amplitude after 11 years of operation at LEP.