TITLE:   GCN CIRCULAR
NUMBER:  35114
SUBJECT: GRB 231117A: 10 GHz VLA detection
DATE:    23/11/19 03:49:13 GMT
FROM:    Genevieve Schroeder at Northwestern University <genevieveschroeder2023@u.northwestern.edu>

G. Schroeder (Northwestern), W. Fong, T. Laskar (Utah) report:

"We observed the position of the short GRB 231117A (Laha et al., GCN 35071,
Navaneeth et al., GCN 35072, Cattaneo et al., GCN 35075, Svinkin et al.,
GCN 35079, Cheung et al., GCN 35081) with the Karl G. Jansky Very Large
Array (VLA) under program 23A-296 (PI: Schroeder) beginning on 2023 Nov.
17.98 UT (0.85 days post-burst) for 0.75 hours at a mean frequency of 10
GHz.

We confirm the presence of a radio source consistent with the location of
the putative optical afterglow and host galaxy (Yang et al. GCN 35083,
Rastinejad et al., GCN 35087, Gompertz & Ackley, GCN 35088, Kumar et al.,
GCN 35089, Andreoni et al., GCN 35099, Kilpatrick et al., GCN 35102, Chen
et al. 35105). We measure a flux density of ~190 uJy, resulting in a radio
luminosity of ~4e29 erg/s/Hz, consistent with typical radio luminosities of
SGRB radio afterglows (Laskar et al. 2022).

Our measured flux density is somewhat fainter than the 9 GHz flux with ATCA
reported by Rhodes et al. (GCN 35097). While the ATCA observations occurred
at a slightly earlier mid-time of 0.54 days than our VLA observations, we
cannot make a strong statistically significant claim regarding fading
between the two observations at this time.

We thank the VLA staff for quickly approving and executing these
observations. Further observations are planned to assess the nature of the
radio source."
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