Speaker
Description
The Atmospheric Lidar (ATLID) onboard the Earth Cloud, Aerosol and Radiation Explorer (EarthCARE) has been repeatedly observed by the Fluorescence Detectors of the Pierre Auger Observatory. Side-scattered ultraviolet light from ATLID laser pulses is recorded by the Auger fluorescence telescopes, which are primarily designed to measure the longitudinal development of extensive air showers initiated by ultra-high-energy cosmic rays. These measurements enable a precise reconstruction of the atmospheric trajectory of the laser beam over the Observatory and provide a unique opportunity for systematic studies of the local atmospheric aerosol content. Furthermore, EarthCARE laser tracks can be observed at the Telescope Array Experiment in the USA within a few days during the same moon cycle, opening the possibility for a direct cross-calibration of the energy scales of the two cosmic-ray observatories. We present first reconstruction results from ATLID observations following EarthCARE’s launch in 2024. These results highlight the potential of satellite-based lidar observations to support calibration and atmospheric characterization efforts at the Pierre Auger Observatory.