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Frequency dependent radio structure of the gravitational lens system B0218+357

Alok R. Patnaik·Richard W. Porcas
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Abstract

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 milliarcsec to 5 milliarcsec 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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Alok R. Patnaik, Richard W. Porcas. 1998-03-23. Frequency dependent radio structure of the gravitational lens system B0218+357. https://arxiv.org/abs/astro-ph/9803264

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