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arXiv · 0802.4148

A Multi-epoch VLBI Survey of the Kinematics of Caltech-Jodrell Bank Flat-Spectrum Sources, Part II: Analysis of the Kinematics

Abstract

Context: This is the second of a series of papers presenting VLBI observations of the 293 Caltech-Jodrell Bank Flat-Spectrum (hereafter CJF) sources and their analysis. Aims: To obtain a consistent motion dataset large enough to allow the systematic properties of the population to be studied. Methods: We present the detailed kinematic analysis of the complete flux-density limited CJF survey. We computed 2-D kinematic models based on the optimal model-fitting parameters of multi-epoch VLBA observations. This allows us to calculate not only radial, but also orthogonal motions, and thus to study curvature and acceleration. Statistical tests of the motions measured and their reliability have been performed. A correlation analysis between the derived apparent motions, luminosities, spectral indices, and core dominance and the resulting consequences is described. Results: With at least one velocity in each of 237 sources, this sample is much larger than any available before and allows a meaningful statistical investigation of apparent motions and any possible correlations with other parameters in AGN jets. Conclusions: This AGN survey provides the basis for any statistical analysis of jet and jet-component properties.

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S. Britzen, R. C. Vermeulen, R. M. Campbell, G. B. Taylor, T. J. Pearson, A. C. S. Readhead, W. Xu, I. W. Browne, D. R. Henstock, P. Wilkinson. 2008-02-28. A Multi-epoch VLBI Survey of the Kinematics of Caltech-Jodrell Bank Flat-Spectrum Sources, Part II: Analysis of the Kinematics. https://doi.org/10.1051/0004-6361:20077717

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