Tim Niggemann III. Physikalisches Institut A, RWTH Aachen University

The Silicon Photomultiplier Telescope FAMOUS for the Fluorescence Detection of UHECRs(pdf)

An established technique for the measurement of ultra-high-energy-cosmic-rays is the detection of fluorescence light induced by extensive air showers in the atmosphere of the Earth by means of telescopes equipped with photomultiplier tubes. Silicon photomultipliers (SiPMs) are very robust, novel photon detectors which promise a high photon-detection-efficiency which outperforms conventional photomultiplier tubes. Drawbacks like a high thermal-noise-rate and correlated noise are currently successfully addressed by the manufactures. FAMOUS is a 64 SiPM pixel and 12 ° field of view refracting telescope of which the main optical element is a Fresnel lens of 50 cm diameter and focal length. Winston cones are used to increase the sensitive area of the SiPMs, and the frontend electronics automatically regulates the bias voltage to correct for the temperature dependency. We present the first working version of FAMOUS with a focal plane prototype providing seven active pixels.