TITLE:   GCN CIRCULAR
NUMBER:  43471
SUBJECT: GRB 251202A: further radio observations with the VLA
DATE:    26/01/20 16:19:41 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 11:52:30 UT on 2025 December 6 (T_mid = 4.45 days post-burst)
and at 11:34:42 UT on 2025 December 11 (T_mid = 9.43 days
post-burst) the Karl G. Jansky VLA observed the field of
GRB 251202A / EP251202A (Fermi GBM team, GCN 42933, 42957;
Einstein Probe team, GCN 42937, GCN 42946; AstroSat CZTI
collaboration, GCN 42967; Insight-HXMT team, GCN 42970;
SVOM team, GCN 42997) in three bands, with central frequencies
of 6, 10 and 15 GHz.

The standard 3C286 was used as bandpass and flux density
calibrator, while J0818+4222 was used as phase calibrator.

From a preliminary analysis, the radio source coincident with
GRB 251202A (Giarratana et al., GCN 43128) is detected at all
frequencies:

================================================================
T_mid	Freq	Peak	r.m.s.	Beam		PA
[days]	[GHz]	[uJy/b]	[uJy/b]	[arcsec^2]	[deg]
================================================================
4.45	6	99	7	1.07x1.02	54
4.45	10	169	7	0.72x0.60	65
4.45	15	296	9	0.45x0.42	34
9.43	6	118	7	1.06x0.95	-76
9.43	10	219	7	0.69x0.58	89
9.43	15	338	8	0.44x0.39	-74
================================================================

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.