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Obscuration of the Parsec Scale Jets in the Compact Symmetric Object 1946+708

A. B. Peck·G. B. Taylor·J. E. Conway
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Abstract

We present results of VLA and VLBA observations of the 1.420 GHz neutral hydrogen absorption associated with the Compact Symmetric Object 1946+708 (z=0.101). We find significant structure in the gas on parsec scales. The peak column density in the HI (N_HI~2.2x10^23 cm^-2 (T_s/8000K)) occurs toward the center of activity of the source, as does the highest velocity dispersion (FWHM~350 \kms). In addition, we find that the continuum spectra of the various radio components associated with these jets strongly indicate free-free absorption. This effect is particularly pronounced toward the core and inner components of the receding jet, suggesting the presence of a screen local to the source, perhaps part of an obscuring torus.

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A. B. Peck, G. B. Taylor, J. E. Conway. 1999-03-15. Obscuration of the Parsec Scale Jets in the Compact Symmetric Object 1946+708. https://doi.org/10.1086/307535

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