Intercontinental VLBI observations of theta 1 Orionis A.
Abstract
This paper presents recent VLBI observations of the variable nonthermal radio source associated with the star Theta(1) Ori A obtained at 6 cm with the European VLBI Network and with the VLA in the phased mode. The total VLA flux density of the source is now 24 mJy. The source is detected with high S/N on the EVN baselines. On the transatlantic baseline there is a marginal detection with low S/NB. A Gaussian fit to the visibilities yields an angular diameter of not less than 1.3 mas. The corresponding brightness temperature is not more than 5.2 x 10 exp 8 K. All the available for VLA flux density measurements of Theta(1) Or A are examined as a function of phase of the binary system. The results indicate one main peak occurring shortly after perioastron and steadier emission elsewhere.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- August 1991
- Bibcode:
- 1991A&A...248..453F
- Keywords:
-
- B Stars;
- Radio Sources (Astronomy);
- T Tauri Stars;
- Very Long Base Interferometry;
- Brightness Temperature;
- Light Curve;
- Radio Emission;
- Very Large Array (Vla);
- Astrophysics