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تسجيل مستخدم جديدThe Youngest Lobe-Dominated Radio Sources
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I. Owsianik
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We present an analysis of multi-epoch global VLBI observations of the Compact Symmetric Objects: 2352+495 and 0710+439 at 5 GHz. Analysis of data spread over almost two decades shows strong evidence for an increase in separation of the outer components of both sources at a rate of ~0.2 h^{-1} c (for q_{0}=0.5 and H_{0}=100 h kms^{-1} Mpc^{-1}). Dividing the overall sizes of the sources by their separation rates implies that these Compact Symmetric Objects have a kinematic age < 10^{4} years. These results (and those for other CSOs) strongly argue that CSOs are indeed very young sources and that they are probably evolve into the much larger classical doubles.
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We present the results of the first X-ray study of a sample of 16 young radio sources classified as Compact Symmetric Objects (CSOs). We observed six of them for the first time in X-rays using {it Chandra}, re-observed four with the previous {it XMM-
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