Next-Generation Triggering: A Novel Event-Level Approach

TL;DR

This paper introduces novel event-level radio trigger methods for cosmic-ray detectors like GRAND, improving the ability to distinguish true air shower signals from background noise using advanced reconstruction and footprint analysis techniques.

Contribution

It presents new event-level trigger approaches, including an upgraded wave front reconstruction and footprint analysis, tailored for GRAND and applicable to other radio detection systems.

Findings

Enhanced background rejection demonstrated on simulated and real data

Improved sensitivity potential for air shower detection

Preliminary results guide future implementation and optimization

Abstract

Large-scale cosmic-ray detectors like the Giant Radio Array for Neutrino Detection (GRAND) are pushing the boundaries of our ability to identify air shower events. Existing trigger schemes rely solely on the timing of signals detected by individual antennas, which brings many challenges in distinguishing true air shower signals from background. This work explores novel event-level radio trigger methods specifically designed for GRAND, but also applicable to other systems, such as the Radio Detector (RD) of the Pierre Auger Observatory. In addition to an upgraded plane wave front reconstruction technique, we introduce orthogonal and complementary approaches that analyze the radio-emission footprint, the spatial distribution of signal strength across triggered antennas, to refine event selection. We test our methods on mock data sets constructed with simulated showers and real background noise measured with the GRAND prototype, to assess the performance potential in terms of sensitivity and background rejection in GRAND. Our preliminary results are a first step to identifying the most discriminating radio signal features at event-level, and optimizing the techniques for future implementation on experimental data.