High Efficiency Gaseous Tracking Detector for Cosmic Muon Radiography

Figure 15

Time dependence of relevant operational parameters during 6 days of data taking in outdoor conditions. Temperature variations up to 25°C were sustained (a), with not more than 10% mean amplitude changes (due to partial compensation of the anode HV). The tracking efficiency was consistently high, shown in (c), during the whole period (note the scale on (c) starts at 99.5%).

(a)

(b)

(c)