Simultaneous observations of multiple ELVES and SPRITES at the Pierre Auger Observatory

TL;DR

This paper reports on simultaneous multi-transient observations of ELVES and SPRITES at the Pierre Auger Observatory, utilizing new camera setups and an automated detection algorithm to enhance understanding of upper atmospheric light phenomena.

Contribution

It introduces a new multi-instrument observational approach and an automated detection algorithm for simultaneous SPRITES and ELVES detection.

Findings

First simultaneous detection of SPRITES and ELVES with multiple instruments.

Implementation of a Python-based DBSCAN algorithm for automatic transient detection.

Enhanced spatial resolution and longer integration times in observations.

Abstract

Since 2014, the Pierre Auger Observatory has exploited a dedicated trigger and its very high time resolution to study ELVES and harvest record samples of multiple ELVES using the Fluorescence Detector (FD). In 2017, after extending the readout of trace lengths to 0.9 ms, we started observing other types of light transients from the base of the ionosphere, such as HALOS, which deserved further investigation. In December 2023 and April 2024, we installed two additional cameras (TLECAMs), which allow us to perform simultaneous detection of these transients with higher space resolution and longer integration times. Here, we present our first simultaneous observations of SPRITES and ELVES by both TLECAMs and FD. Furthermore, we describe the Python algorithm based on DBSCAN to automatically detect SPRITES in the videos recorded by our TLECAMs and acquire data efficiently without needing the FD trigger.