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تسجيل مستخدم جديدImaging HI Absorption toward Symmetric Radio Galaxies - Evidence for a Circumnuclear Torus
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Recent VLBI observations have identified several compact radio sources which have symmetric structures on parsec scales, and exhibit HI absorption which appears to be associated with the active nucleus. These sources are uniquely well suited to investigations into the physics of the central engines, in particular to studies of the kinematics of the gas within 100 pc of the core. In these compact sources, it is reasonable to assume that this circumnuclear material is accreting onto, and ``feeding, the central engine. We present results of HI imaging studies of 3 symmetric radio galaxies which show evidence of a circumnuclear torus.
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We present a study, done with the Australian LBA, of HI absorption for two compact radio galaxies (PKS 1549-79 and PKS 1814-63). In both the radio galaxies, the HI appears to give us information about the environment in which the radio sources are em
bedded, the effect that the ISM can have on the observed characteristics and the possible presence of interaction between the ISM and the radio plasma.
We present results from a search for 21 cm associated HI absorption in a sample of 29 radio sources selected from the Australia Telescope 20 GHz survey. Observations were conducted using the Australia Telescope Compact Array Broadband Backend, with w
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