Obscuration of the Parsec Scale Jets in
نویسندگان
چکیده
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 nd signiicant structure in the gas on parsec scales. The peak column density in the Hi (N HI '2.210 23 cm ?2 (Ts 8000K)) occurs toward the center of activity of the source, as does the highest velocity dispersion ((V FWHM '350 km s ?1). In addition, we nd that the continuum spectra of the various radio components associated with these jets strongly indicate free-free absorption. This eeect 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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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 H i (NHI ≃2.2×10 23 cm( Ts 8000K ) ) occurs toward the center of activity of the source, as does the highest velocity dispersion (∆VFWHM ≃350 km s )....
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