The First AGILE Solar Flare Catalog: updates and new correlation studies

Poster contribution for the European Space Weather Week 2025 held in Umea from October 27 to October 31. Abstract: The Astro-rivelatore Gamma a Immagini LEggero (AGILE) has been a unique and successful space mission of the Italian Space Agency (ASI), with the programmatic and technical contribution of INAF and INFN. During almost 17 years of observations, since the launch on April 23, 2007 to the satellite re-entry on February 14, 2024, AGILE contributed to high-energy astrophysics, terrestrial and solar flare physics with many discoveries and detections. The First AGILE Solar Flare Catalog (A. Ursi et al., 2023) includes AGILE observations of solar flares, detected by the onboard anticoincidence system in the hard X-ray energy range, from 2007 May 1 to 2022 August 31. The catalog includes more than 5000 X-ray, minute-lasting events from 2007 to 2022, a significant number of which cross-related with the official GOES, RHESSI, and Fermi GBM public lists of solar flares. On the other hand, this catalog reports more than 1400 "AGILE only" events, not contained in the GOES official data set, which, after statistical comparisons, are compatible with low-intensity, short-duration solar flares. Besides providing a further data set of solar flares detected in the hard X-ray range, this study allowed to point out two main features: a longer persistence of the decay phase in the high-energy regime, with respect to the soft X-rays, and a tendency of the flare maximum to be reached earlier in the hard X-rays with respect to the soft X-rays. Both these aspects support a two-phase acceleration mechanism of electrons in the solar atmosphere. We provide an overview of a recent update of the AGILE solar flare events, including cross-correlation with a new solar flare catalogue (Archival Solar flaRes catalogue, M. Berretti et al., 2025), which allows us to identify the solar origin for the flares recorded by AGILE. This adds significant value to space weather research for the scientific community.