GCN Circular 34405
Subject
GRB 230812B: Detected Optical Afterglow Candidate
Date
2023-08-13T17:32:55Z (a year ago)
From
Mohammad Odeh at Al Khatim Observatory M44 <mshodeh@gmail.com>
Via
legacy email
Mohammad Odeh, Osama Ghannam, Anas Mohammad, Khalfan Al-Noaimy, and Sameh
Al-Ashi, report on behalf of Al-Khatim Observatory (AKO) operated by the
International Astronomical Center in Abu Dhabi, UAE:
We observed the field of GRB 230812B (Lesage et al., GCN 34387; Scotton et
al., GCN 34392; Page, GCN 34394; Zheng & Filippenko, GCN 34395; Lipunov et
al., GCN 34396; Salgundi et al., GCN 34397; Ackley et al., GCN 34398; Xiong
et al., GCN 34401; Casentini et al., GCN 34002; Frederiks et al., GCN
34403; Mao et al., GCN 34404), with our 0.36m f/7.7 robotic telescope. The
observation was done on 13 August 2023 from 16:15 to 16:47 (UT), about 21.6
hours from the trigger.
We obtained multiple 180-sec exposures in Ic filter. We detected an optical
afterglow candidate at:
R.A. (J2000): 16:36:31.45
Dec. (J2000): +47:51:32.3
That is the same localization of (Zheng & Filippenko, GCN 34395), which is
about 5.5 arcsec from the improved Swift/XRT localization (Page, GCN 34394).
The following observation was calculated using Atlas catalogue as a
reference:
-----------------------------------------------------------------------------
ObsTime (mid), Exposure (sec), Filter, Mag
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2023-08-13T16:32:40Z, 10 x 180s (stacked), Ic, 18.8 +/- 0.21
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The magnitude is not corrected for galactic extinction.