TITLE: GCN CIRCULAR NUMBER: 44235 SUBJECT: GRB 260310A: Continued VLA Multi-frequency Radio Observations DATE: 26/04/08 02:27:55 GMT FROM: Genevieve Schroeder at Cornell University <genevieveschroeder@u.northwestern.edu> G. Schroeder (Cornell), D. A. Perley (LJMU), and T. Laskar (Utah) report on behalf of a larger collaboration: The Karl G. Jansky Very Large Array observed the location of the afterglow (Hinds et al., TNS AstroNote 2026-65; Konno et al., GCN 43974) associated with GRB 260310A (Fermi GBM Team, GCN 43951; Hamburg & Meegan, GCN 43975) using all available receivers from L-band to Q-band, providing nearly continuous spectral coverage from 1 to 50 GHz, as a part of our multi-frequency public campaign (Perley et al., GCN 44160). Observations were carried out on UT 2026-04-04 between 08:42 and 12:19 UT, approximately 25.2 days after the GRB. Preliminary flux densities are: | freq(GHz) | flux(mJy) | |-----------|----------------| | 1.5 | 1.74 +/- 0.06 | | 3 | 5.00 +/- 0.04 | | 6 | 8.39 +/- 0.05 | | 10 | 8.93 +/- 0.12 | | 15 | 8.16 +/- 0.22 | | 22 | 7.34 +/- 0.23 | | 33 | 6.14 +/- 0.19 | | 45 | 5.25 +/- 0.19 | Compared to previous radio observations (Rhodes et al., GCN 44005; Giarratana et al., GCN 44045; Ho et al., GCN 44057; Ho et al., GCN 44134, Perley et al., GCN 44160), the afterglow is brightening at lower frequencies (< 10 GHz) and fading at higher frequencies (> 10 GHz). We thank the NRAO staff for scheduling and executing these observations. Further observations are planned. View this GCN Circular online at https://gcn.nasa.gov/circulars/44235. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...