A radio and infrared exploration around cygnus X-3 (Research note)

Aims. To investigate the possible hot spot nature of two previously detected radio sources in the vicinity of the Cygnus X-3 microquasar. Methods. We present the results of a radio and near infrared exploration of the several arc-minute field around the well known galactic relativistic jet source Cygnus X-3 using the Very Large Array and the Calar Alto 3.5 m telescope. Results. The data on which this paper is based do not support the hot spot hypothesis. Instead, our new observations suggest that these sources are most likely background or foreground objects. None of them appears to be even barely extended, as would be expected if they were part of a bow shock structure. Our near infrared observations also include a search for extended emission in the Bracket. (2.166 mu m) and H-2 (2.122 mu m) lines as possible tracers of shocked gas in the Cygnus X-3 surroundings. The results were similarly negative and the corresponding upper limits are reported.