Forum Springer Astron. Astrophys.
Forum Whats New Search Orders

Astron. Astrophys. 358, 451-461 (2000)

Previous Section Next Section Title Page Table of Contents

5. Superluminal motion

The 8 GHz data allow us to set only an upper limit on the apparent motion of component B: [FORMULA]0.2mas/yr (Pyatunina 1998). However, the higher resolution 43 GHz data do reveal motion of component B as shown in Fig. 15, which presents the separation of component B from the core as a function of time. There is no evidence in the data for non-linear motion within the time interval from 1996.6 to 1997.6 despite the strong bend of the inner jet.

[FIGURE] Fig. 15. Relative separation at 43 GHz of component B from the core versus time.

A linear fit to the data yields an apparent angular separation rate of µ=0.18[FORMULA]0.01 mas/yr, corresponding to an apparent superluminal velocity v=(8.1[FORMULA]0.3)c (Ho=65 km s-1 Mpc-1, qo=0.1). Linear back-extrapolation of the motion of B gives the time of zero separation as [FORMULA]=1994.83[FORMULA]0.06. This epoch, indicated in Fig. 1, corresponds to the local minimum of the total flux density at all frequencies in cycle C3, which agrees with the results of Mutel et al. (1990) and Krichbaum et al. (1998) that new jet components tend to appear at times of local minima in the light curve of a compact radio source.

Previous Section Next Section Title Page Table of Contents

© European Southern Observatory (ESO) 2000

Online publication: June 8, 2000