TITLE: GCN CIRCULAR NUMBER: 43952 SUBJECT: GRB 260208A: radio detection with the VLA DATE: 26/03/10 09:40:09 GMT FROM: Stefano Giarratana at INAF-OAB <s.giarratana@ira.inaf.it> S. Giarratana (INAF-OAB), M. Giroletti (INAF-IRA), G. Ghirlanda (INAF-OAB), N. Di Lalla (Stanford Univ.), N. Omodei (Stanford Univ.), O. S. Salafia (INAF-OAB), L. Nava (INAF-OAB) At 05:24:16 UT on 2026 February 10 (T_mid = 2.04 days post-burst) the Karl G. Jansky VLA observed the field of GRB 260208A (Fermi GBM team, GCN 43635, 43673; Fermi-LAT team, GCN 43645; GECAM team, GCN 43658; Waratkar et al., GCN 43674; Cheung et al., GCN 43675; Kirschner et al., GCN 43896) in three bands, with central frequencies of 6, 10 and 15 GHz. The standard 3C286 was used as bandpass, flux density and phase calibrator. From a preliminary analysis, an unresolved radio source is detected at a position (J2000): RA: 13:38:55.595 +- 0.001 Dec: +33:48:06.12 +- 0.01 consistent with the X-ray (Swift-XRT team, GCN 43652) and optical (Podesta et al., GCN 43640; GOTO collaboration, GCN 43641; SVOM/VT team, GCN 43655; ZTF collaboration, GCN 43657; Dimple et al., GCN 43661; Magnani et al., GCN 43664; Gupta et al., GCN 43665; Volnova et al., GCN 43666, 43770, 43771; Bochenek et al., GCN 43676; Pérez-Fournon et al., GCN 43694; Swift/UVOT team, GCN 43702) position of the transient. The preliminary analysis yields the following results: ================================================================ T_mid Freq Peak r.m.s. Beam PA [days] [GHz] [uJy/b] [uJy/b] [arcsec^2] [deg] ================================================================ 2.04 6 59 7 1.57x0.31 -60 2.04 10 90 8 1.27x0.18 -57 2.04 15 125 10 1.02x0.14 -55 ================================================================ No source is detected with a >3sigma confidence level at the aforementioned position in the VLASS. However, the r.m.s. noise level of the survey at the GRB location is approximately 130 uJy/b. We would like to thank the staff of the VLA for approving, executing, and processing the observations. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. These observations were carried out as part of project SF181027, approved in the framework of the Fermi - NRAO joint program agreement. View this GCN Circular online at https://gcn.nasa.gov/circulars/43952. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...