Radio follow-up of the X-ray transient in NGC 7793
ATel #15744; G. Bruni (INAF-IAPS), R. D. Baldi (INAF-IRA), F. Panessa (INAF-IAPS), L. Hernandez-Garcia (MAS, U. Valparaiso), M. Brightman (Caltech)
on 4 Nov 2022; 09:32 UT
Credential Certification: Gabriele Bruni (gabriele.bruni@inaf.it)
Subjects: Radio, Optical, Black Hole, Neutron Star, Transient
We report on a radio follow-up of the X-ray transient recently detected in NGC 7793 (ATel #15632). VLA observations were carried out on October 27th, 2022, at X-band (8-12 GHz), in C configuration. The angular resolution was 5.9"x2.3", slightly larger than the nominal one due to the low declination of the source. The field of view included the entire host galaxy structure.
A recent Chandra follow-up of the X-ray transient (ATel #15737) provides an improved position (0.6" uncertainty), showing a significant offset from the nucleus of NGC 7793. We do not detect radio emission at this position, resulting in a 3-sigma upper limit of 18 uJy/beam. An emitting region is visible starting ~3" towards west from the transient position, with an angular size of about 13". An overplot with archival HST images shows a correspondence with optical emission, possibly implying a star-forming region in an inner arm of the host galaxy.
The two discussed images, reporting also the Swift/XRT and Chandra positions, are retrievable at the following links:
VLA image
VLA+HST image
