RT Journal Article T1 The Stereoscopic Analog Trigger of the MAGIC Telescopes A1 López Moya, Marcos A1 otros, ... AB The current generation of ground-based imaging atmospheric Cherenkov telescopes (IACTs) operate in the very-high-energy (VHE) domain from similar to 100 GeV to similar to 100 TeV. They use electronic digital trigger systems to discern the Cherenkov light flashes emitted by extensive air showers (EASs), from the overwhelming light of the night sky (LoNS) background. Near the telescope energy threshold, the number of emitted Cherenkov photons by gamma-ray-induced EASs is comparable to the fluctuations of the LoNS and the photon distribution at the Cherenkov-imaging camera plane becomes patchy. This results in a severe loss of effectiveness of the digital triggers based on combinatorial logic of thresholded signals. A stereoscopic analog trigger system has been developed for improving the detection capabilities of the Major Atmospheric Gamma-ray Imaging Cherenkov (MAGIC) telescopes at the lowest energies. It is based on the analog sum of the photosensor electrical signals. In this article, the architectural design, technical performances, and configuration of this stereoscopic analog trigger, dubbed "Sum-Trigger-II," are described. PB IEEE-Inst Electrical Electronics Engineers Inc SN 0018-9499 YR 2021 FD 2021-07 LK https://hdl.handle.net/20.500.14352/4443 UL https://hdl.handle.net/20.500.14352/4443 LA eng NO Artículo firmado por 21 autores. This work was supported in part by German Bundesministerium fur Bildung und Forschung (Federal Ministry of Education and Research) and Max-Planck-Gesellschaft (Max Planck Society), in part by Italian Istituto Nazionale di Fisica Nucleare (National Institute for Nuclear Physics), and in part by Spanish Ministerio de Asuntos Economicos y Transformacion Digital (Ministry of Economic Affairs and Digital Transformation). NO German Bundesministerium fur Bildung und Forschung (Federal Ministry of Education and Research) NO Max-Planck-Gesellschaft (Max Planck Society) NO Italian Istituto Nazionale di Fisica Nucleare (National Institute for Nuclear Physics) NO Spanish Ministerio de Asuntos Económicos y Transformación Digital (Ministry of Economic Affairs and Digital Transformation) DS Docta Complutense RD 6 abr 2025