4 v 1 2 3 M ar 1 99 8 Frequency dependent radio structure of the gravitational lens system B 0218
نویسندگان
چکیده
We present multi-frequency radio continuum VLBI observations of the gravitational lens system B0218+357 carried out using a global VLBI network and the VLBA. The source has been observed with resolutions from 0.2 mas to 5 mas and displays interesting structure. The spectral properties of various components show that the lensed object is a standard flat spectrum radio source which has many self-absorbed components. Based on the flux ratio of the lensed images as a function of frequency we propose a simple model for the background radio source.
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