Extended Data Figure 5: Overview of the gas detectors (CEA).
From: Discovery of a big void in Khufu’s Pyramid by observation of cosmic-ray muons
a, Design of a telescope (without its cover) showing the four detectors, the electronics box, the battery and the gas bottles. b, Design of the multiplexed Micromegas detector. c, Principle of a Micromegas detector, showing the ionization and amplification of the signal initiated from a charged particle (dotted array). d, Layout of the detector with the micromesh in red, the resistive strip film in blue, and the Y and X copper readout strips in yellow. HV, high voltage; ADC, analogue digital converter. e–g, Amplitude variation of a detector in the Alhazen telescope as a function of time for two previous campaigns (ScanPyramids missions 1 and 2) and the one reported here (g), showing the effect of the patented feedback. Large variations (as observed in e and f) can lead to inefficiency or degraded resolution, and are totally absent from the data of this paper. The only step observed in g corresponds to a manual change of the target amplitude. h, Typical signal recorded in a detector, where each line corresponds to an electronic channel.
