Low-latency NuMI Trigger for the CHIPS-5 Neutrino Detector

TL;DR

This paper introduces a low-latency, high-precision triggering system for the CHIPS-5 neutrino detector, enabling real-time neutrino spill notifications with sub-nanosecond accuracy using open-source tools.

Contribution

It presents a novel, cost-effective low-latency trigger system built on existing infrastructure, achieving sub-nanosecond timing precision for neutrino detection.

Findings

Achieved 96% efficiency in neutrino spill notification

Provided notifications 610 ms before neutrino spills on average

Enabled real-time analysis and bandwidth reduction

Abstract

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 NOvA 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 $610 \pm 330\text{ ms}$ 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.