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Spectral distributions in compact radio sources I. Imaging with VLBI data

A. P. Lobanov
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Abstract

We discuss a technique for mapping the synchrotron turnover frequency distribution using nearly simultaneous, multi--frequency VLBI observations. The limitations of the technique arising from limited spatial sampling and frequency coverage are investigated. The errors caused by uneven spatial sampling of typical multi--frequency VLBA datasets are estimated through numerical simulations, and are shown to be of the order of 10%, for pixels with the deconvolution SNR~7. The fitted spectral parameters are corrected for the errors due to limited frequency coverage of VLBI data. First results from mapping the turnover frequency distribution in 3C345 are presented.

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A. P. Lobanov. 1998-04-10. Spectral distributions in compact radio sources I. Imaging with VLBI data. https://doi.org/10.1051/aas%3A1998446

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