TITLE:   GCN CIRCULAR
NUMBER:  46255
SUBJECT: EP261006a: VLA Radio Detection
DATE:    26/11/13 19:35:10 GMT
FROM:    Sarah Opoku at Cornell University <syo6@cornell.edu>

Sarah Y. Opoku (Cornell), Daniel A. Perley (LJMU), Anna Y. Q. Ho (Cornell):

We observed the field of the X-ray transient EP261006a (Lao et al., GCN 45826) using the Karl G. Jansky Very Large Array (VLA) at a central frequency of 10 GHz (X-band) on four epochs: 2026-10-09, 2026-10-12, 2026-10-20, and 2026-10-31. 

No significant emission was detected at the reported position of the X-ray (Eyles-Ferris et al., GCN 45831, Monsalves et al., GCN 45857) and optical (Eyles-Ferris et al., GCN 45831; Wu et al., GCN 45852; Bochenek et al., GCN 45853; Chen et al., GCN 45854) counterparts in the first three epochs, with a representative 3σ upper limit of 26 µJy. The third epoch shows a marginal (~3 sigma) detection at the source position.

In the most recent observation (2026-10-31), we securely detect a point source at a position of RA = 01:27:10.006, Dec = +12:53:26.67 (J2000), with an uncertainty of 0.1 arcseconds and a flux density of 42.2 ± 4.5 µJy.  This position is coincident with the nucleus of the host galaxy (Gaia DR3 2587044864659595392). Comparison with the earlier epochs indicates that the radio source is brightening.

Further multi-frequency radio observations are planned. We thank the VLA staff for rapidly scheduling and executing these observations.