The LST-1 issues its first ATel with the detection of a BL Lacertae
Tomohiro Inada (ICRR, University of Tokyo)
The prototype Large-Sized Telescope, the LST-1, has issued an Astronomer’s Telegram (ATel) after detecting very high-energy gamma-ray emission from a BL Lacertae! The source, a type of an Active Galactic Nucleus, was observed on the night of July 11 during the commissioning of the telescope, located at the CTAO northern hemisphere site on La Palma (Spain). Despite non-optimal weather conditions, early analysis shows detection of gamma rays with a significance of 8 sigma at 100 GeV. This new detection proves once again the LST-1’s low-energy performance and ability to detect distant galaxies. The preliminary analysis was performed by Daniel Morcuende (Universidad Complutense de Madrid) and Rubén López-Coto (INFN-Padova).