GCN Circular 36263

H. Kumar, D. Hiramatsu, E. Berger, A. Villar, K. D. Soto, S. K. Yadavalli, M. Hussaini, A. Gagliano, C. Ransome (Harvard) report:


We used the LDSS-3 imager on the 6.5m Magellan Clay telescope to carry out a search for an optical counterpart to the gravitational wave event S240422ed (GCN #36236). A series of 120-second i-band images were obtained starting about 5 hours after the trigger, targeting galaxies coincident with the 3D localization of the event as described by Piro et al. (GCN #36244).

Inspecting the images in the vicinity of galaxies within the localization volume, in comparison to PS1/3pi images, we identify two sources (one low significance):
 
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RA (J2000) | Dec (J2000)| Filter | Mag(AB)| Remarks
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07:57:41.422 | -21:53:15.12 | i | ~21.5 | S/N ~ 8
08:06:04.799 | -22:27:03.71 | i | ~21.7 | S/N < 5
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These sources are slightly fainter than the reference images from PS1/3pi, and we therefore cannot comment about their transient nature. There are no minor planets around these coordinates. Further observations of these candidates are planned, and we encourage additional follow-up.

We thank Marcelo Mora, Povilas Palunas, and the LCO staff for rapid execution of these observations.