GCN Circular 37029
Subject
EP240802a: Montarrenti Observatory optical upper limit
Date
2024-08-04T20:41:01Z (10 months ago)
From
Simone Leonini at Montarrenti Observatory (Siena, Italy) <s.leonini@iol.it>
Via
Web form
S. Leonini, M. Conti, P. Rosi, L.M. Tinjaca Ramirez (Montarrenti Observatory, Siena, Italy, part of UAI/SSV-GRB section), M.G. Dainotti (National Astronomical Observatory of Japan), Y. Niino (Tokyo University, Institute of Astronomy), K. Kalinowski (Aarhus University, Department of Physics and Astronomy) and B. De Simone (Universita' degli Studi Di Salerno) report:
we observed the field of the fast X-ray transient EP240802a (Einstein Probe, GCN 37019, Wang et al.) probably associated to GRB 240802A (GCN 37018, G. Waratkar et al.) with the automated and remoted 0.53m Ritchey-Chretien telescope at Montarrenti Observatory (Siena, Italy, IAU code C88).
The observations were started at 2024-08-03 22:38:41 UT (approximately 36 hours after the discovery of the X-ray transient) stacking 45x40s calibrated Rc-band CCD images.
We have not found any optical transient candidate within the error-box of the EP mission position with the following upper limit:
MJD Filter Limit Err
60526.4544 Rc > 20.47 +/-0.07
consistent with other follow-up observations (GCN 37021, A. Aryan et al.; GCN 37023, U. Quadri et al.)
Magnitude was calibrated with the nearby PanSTARRS stars converted using Lupton (2005) equations. No correction for galactic dust extinction was applied.