The MAGIC and LST-1 telescopes, located at the Roque de los Muchachos Observatory on
La Palma, operate dedicated On-Site Analysis (OSA) pipelines that provide rapid, automated
processing of observational data. These systems produce high-level data products just a few hours
after observations are completed, enabling quick-look analyses, next-day data quality assessments,
and rapid-response science such as flare detection and Target of Opportunity follow-ups. OSA
pipelines have been in continuous operation since 2012 for MAGIC and since 2021 for LST-1,
automatically processing nightly data using the standard analysis chain. The experience gained
from both systems provides essential lessons for the development of Cherenkov Telescope Array
Observatory’s (CTAO’s) on-site analysis, demonstrating the practical and scientific benefits of fast
data processing in Cherenkov telescopes.

