GCN Circular 33695

Y.-D. Hu, E. Fernandez-Garcia, A. J. Castro-Tirado, I. Perez-Garcia, M.D. Caballero-Garcia, R. Sanchez-Ramirez, S. Guziy (IAA-CSIC), D. Hiriart and W. H. Lee (UNAM), C. J. Perez del Pulgar (UMA) and I. M. Carrasco-Garcia (SMA) and I. H. Park (SKKU), on behalf of a larger collaboration, report:

Following the detection of GRB 230427A by Swift (Troja et al. GCNC 33687), the BOOTES-5/JGT 0.6m robotic telescope at observatorio Astronomico Nacional in San Pedro Martir (Mexico) automatically observed the GRB location starting on Apr. 27, 10:35:34 UT (~ 282 s after trigger). A series of images in clear filter were gathered. A new optical transient was found within the enhanced Swift/XRT position (Beardmore et al. GCNC 33688) for which we measure a magnitude of 20.6 +- 0.2 on the co-added 10 s x 54 image, which is consistent with the detection of Swfit/UVOT (Troja et al. GCNC 33687).

We thank the staff at Observatorio Astronomico Nacional in San Pedro Martir for their excellent support.