Low-latency NuMI trigger for the Chips-5 neutrino detector

• Published in: Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment Accelerators, spectrometers, detectors and associated equipment, 2022-05, Vol.1030 (C), p.166513, Article 166513
• Main Authors: Bash, Simeon, Cesar, John, Deuerling, Greg, Dodwell, Thomas, Germani, Stefano, Mánek, Petr, Niner, Evan, Norman, Andrew, Thomas, Jennifer, Tingey, Josh, Wilcer, Neil
• Format: Article
• Language: English
• Subjects: NuMI beam; Software engineering; Time synchronisation; Trigger; Water Cherenkov detectors
• ISSN: 0168-9002; 1872-9576
• DOI: 10.1016/j.nima.2022.166513

The Chips R&D Project aims to develop affordable large-scale water Cherenkov neutrino detectors for underwater deployment. In 2019, a 5kt prototype detector Chips-5 was deployed in northern Minnesota to potentially study neutrinos generated by the NuMI beam. This paper presents the dedicated low-latency triggering system for Chips-5 that delivers notifications of neutrino spills from the Fermilab accelerator complex to the detector with sub-nanosecond precision. Building on existing NOνA infrastructure, the time distribution system achieves this using only open-source software and conventional computing and network elements. In a time-of-flight study, the system reliably provided advance notifications 610±330ms prior to neutrino spills at 96% efficiency. This permits advanced analysis in real-time as well as hardware-assisted triggering that saves data bandwidth and reduces DAQ computing load outside time windows of interest.