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

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.