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Restarting activity in radio galaxies

L. Lara·G. Giovannini·W. D. Cotton·L. Feretti·J. M. Marcaide·I. Marquez·G. B. Taylor·T. Venturi
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Abstract

We present observations of two radio galaxies, J1835+620 and 3C338, both with signs of having passed through different stages of core activity. The former presents two symmetric and bright components within a typical FR II structure, possibly resulting from two distinct phases of activity; the latter is a FR I radio galaxy with two separated regions with different age properties, possibly due to a switch-off and -on cycle in its core. In both sources, the optical counterpart lies in a group of galaxies with indications of mutual interaction, a scenario often invoked to explain triggering of core activity.

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L. Lara, G. Giovannini, W. D. Cotton, L. Feretti, J. M. Marcaide, I. Marquez, G. B. Taylor, T. Venturi. 1999-09-13. Restarting activity in radio galaxies. https://doi.org/10.1016/s1387-6473(01)00161-0

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