TITLE: GCN CIRCULAR NUMBER: 26067 SUBJECT: GRB 191024A: VLT/X-shooter optical observations DATE: 19/10/24 13:48:45 GMT FROM: Dong Xu at NAOC/CAS D. Xu (NAOC), J.T. Palmerio (CNRS - Obs. de Paris/GEPI), D. B. Malesani (DTU space), K. E. Heintz (Univ. of Iceland), N. R. Tanvir (Univ. Leicester), J. P. U. Fynbo (DAWN/NBI), A. J. Levan (Radboud Univ.), G. Pugliese (Univ. Amsterdam), C. Kouveliotou (GWU, APSIS), report on behalf of the Stargate collaboration: We observed the field of GRB 191024A (Page et al., GCN 26063) using the ESO VLT UT2 (Kueyen) equipped with the X-shooter camera. Observations started at 06:14:13 UT on 2019-10-14 (i.e., 1.523 hr after the BAT trigger) and 3x40 s, 3x30 s , 3x60 s frames were obtained in the Sloan g- / r- / z- bands, respectively. No optical source is detected in our stacked image within the enhanced XRT error circle (Beardmore et al., GCN 26064), down to a limiting magnitude of r ~ 24.3 AB mag. However, there exist two sources just outside and south of the XRT error circle in all the stacked g-, r-, and z-band images. Their coordinates and magnitudes are as follows S1 R.A.(J2000) = 0:40:27.360 Dec.(J2000) = -67:08:44.800 Distance from the XRT center: 2.8" m(r) ~ 24.1 AB mag S2 R.A.(J2000) = 00:40:27.480 Dec.(J2000) = -67:08:45.800 Distance from the XRT center: 3.6" m(r) ~ 23.7 AB mag Due to small FOV, the magnitudes are calculated using only one DSS-2 reference star at R.A. (J2000) = 00:40:29.68 and Dec. (J2000) = -67:08:43.99 with R1=19.68. And due to only one epoch of photometry, it is not clear if either of the two sources is related to the burst. Further observations are required to check for variability. We acknowledge excellent support from the ESO observing staff in Paranal, in particular Trystyn Berg and Marcela Espinoza. [GCN OPS NOTE(24oct19): Per author's request, "Marcela Espinoza" was added to the last sentence.]