TITLE: GCN CIRCULAR NUMBER: 40331 SUBJECT: GRB 250502A: AKO Optical Afterglow Detection DATE: 25/05/03 08:39:13 GMT FROM: Mohammad Odeh at Al Khatim Observatory M44 mshodeh@gmail.com

Mohammad Odeh (Al-Khatim Observatory, AKO, operated by the International Astronomical Center in Abu Dhabi, UAE), and Nidhal Guessoum (American University of Sharjah, UAE), report:

We observed the field of GRB 250502A detected by SVOM (Wang et al., GCN 40313), using our 0.36m f/7.7 robotic telescope. The observation session began on 02 May 2025 at 15:40 UT, with a midpoint at 16:43 UT, approximately 8 hours after the trigger.

We obtained multiple 180-second exposures using the Ic filter. The optical afterglow was marginally detected at:

R.A. (J2000): 13:46:05.4

Dec. (J2000): -10:45:32.4

Our detection is consistent with the results of (Rakotondrainibe et al., GCN 40315; An et al., GCN 40319; Li et al., GCN 40320; Ghosh et al., GCN 40322; de Ugarte Postigo et al., GCN 40328; Pérez-Fournon et al., GCN 40330).

The following observation was calculated using the Atlas catalogue as a reference:

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ObsTime (mid), Exposure (sec), Filter, Mag

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2025-05-02T16:43:29Z, 40 x 180s (stacked), Ic, 19.74 +/- 0.31

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The magnitude is not corrected for galactic extinction.

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