TITLE: GCN CIRCULAR NUMBER: 40180 SUBJECT: GRB 250419A: AKO Optical Afterglow Detection DATE: 25/04/19 19:19:16 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 Shaikha Alshamsi, and Nidhal Guessoum (American University of Sharjah, UAE), report:

We observed the field of GRB 250419A detected by SVOM (Wang et al., GCN 40168), using our 0.36m f/7.7 robotic telescope. The observation session began on 19 April 2025 at 15:49 UT and continued until 18:48 UT, with a midpoint at 17:18 UT, approximately 14.8 hours after the trigger.

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

R.A. (J2000): 13:29:37.30

Dec. (J2000): +07:02:27.7

Our detection is consistent with the results of (López et al., GCN 40169; Xin et al., GCN 40170; Zheng et al., GCN 40171; Kumar et al., GCN 40172; Lipunov et al., GCN 40179).

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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2025-04-19T17:18:06Z, 57 x 180s (stacked), Ic, 18.7 +/- 0.16

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The magnitude is not corrected for galactic extinction.

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