Speakers
Description
In this talk, we present an ongoing development for the next generation of fully packaged digital photodetectors based on a light-trapping mechanism called DELTA, Digital End-to-end Light Trap Assembly. The end-to-end development covers incident photons up to the digital signals saved to disk. DELTA is both a class of photodetectors, each tailored to its specific application within a common design, and an R&D platform in which all components are developed together across labs and universities. Main topics of R&D for the DELTA detector follow this chain: large-area photo-collectors that trap light inside (wavelength-shifting films and total-internal-reflection light traps), small-area photosensors optically coupled to the photo-collectors, on-board cold signal processing and digitization, and finally, laser photonics for power and signal transmission over fiber. The goal is to prototype this next-generation DELTA photodetector using the resources available under CPAD RDC2 working packages (WP1 and WP2).
The DELTA photodetector has final target applications in future noble liquid experiments, as well as VUV light detection in astro-particle physics, astronomy, nuclear particle physics, medical physics, and national security where compact light detectors, large-scale deployment, or harsh environments such as cryogenics, high voltage, and radio purity are called for. Its first use case is APEX, the photon detection system integrated in the field cage of DUNE Phase-II, from protoDUNE-III (2029–30) to the Far Detector 3. This proposal is motivated by emerging technologies in many fields, including microelectronics, laser photonics, and material science.
The reference design and its simulated performance, the options under study for each block, and recent progress will be presented. Recent progress includes spray-deposited and industrial vacuum-deposited pTP coatings (companion talks in the RDC2 sessions), cold tests of SiPM candidates, second-generation power over fiber at 1470 nm, and a cross-lab cryogenic ASIC initiative for the DELTA/APEX readout.