Flasher and muon-based calibration of the GCT telescopes proposed for the Cherenkov Telescope Array

摘要

The GCT is a dual-mirror Small-Sized-Telescope prototype proposed for theCherenkov Telescope Array. Calibration of the GCT's camera is primarilyachieved with LED-based flasher units capable of producing $\sim4$ ns FWHMpulses of 400 nm light across a large dynamic range, from 0.1 up to 1000photoelectrons. The flasher units are housed in the four corners of thecamera's focal plane and illuminate it via reflection from the secondarymirror. These flasher units are adaptable to allow several calibrationscenarios to be accomplished: camera flat-fielding, linearity measurements (upto and past saturation), and gain estimates from both single pe measurementsand from the photon statistics at various high illumination levels. In theseproceedings, the performance of the GCT flashers is described, together withongoing simulation work to quantify the efficiency of using muon rings as anend-to-end calibration for the optical throughput of the GCT.