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arXiv · 1301.2216

Searching for evidence of jet-cloud interaction in radio galaxies. First results for 3C 381

V. Reynaldi·C. Feinstein
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Abstract

We present results of Gemini spectroscopy and Hubble Space Telescope imaging of the 3C~381 radio galaxy. Possible ionising mechanisms for the Extended Emission-Line Region were studied through state-of-the-art diagnostic analysis employing line-ratios. Photoionisation from the central engine as well as mixed-medium photoionisation models fail in reproducing both the strengths and the behaviour of the highest-excitation lines, such as [NeV]3424, HeII, and [OIII}]5007, which are measured at very large distances from the AGN. Shock-ionisation models provide a better fit to the observation. Expanding shocks with velocities higher than 500 km/s are capable of reaching the observed intensity ratios for lines with different ionisation states and excitation degrees. This model also provide a direct explanation of the mechanical energy input needed to explain the high-velocity line-splitting observed in the velocity field.

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V. Reynaldi, C. Feinstein. 2013-01-10. Searching for evidence of jet-cloud interaction in radio galaxies. First results for 3C 381. https://doi.org/10.1093/mnras/stt042

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