IRAS04210+0400: Modeling the optical spectra from flaring large scale jets

W. Steffen; A. J. Holloway; A. Pedlar

doi:10.1093/mnras/282.4.1203

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arXiv · astro-ph/9605049

IRAS04210+0400: Modeling the optical spectra from flaring large scale jets

W. Steffen·A. J. Holloway·A. Pedlar

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Abstract

The emission-lines in the active galaxy IRAS\,0421+0400 show a dramatic ($\sim$\,900\kms) increase in the velocity spread at the position of radio hot-spots which are located at the beginning of extended radio lobes. We study a simple geometric model of an opening outflow which reproduces the structure found in the long-slit emission-line spectrum of the hot-spot regions. The predicted bifurcations in the optical image structure of these regions is confirmed by deep \oiii\,line-imaging. We propose that this phenomenon is the result of a jet emerging from the galaxy through the boundary between the interstellar and intergalactic medium. A similar model has previously been suggested as an explanation for wide angle tail radio sources (WAT's). If our model proves to be correct in more detailed future observations, then IRAS\,0421+0400 provides a unique possibility to study the flaring jet phenomenon at optical wavelengths.

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W. Steffen, A. J. Holloway, A. Pedlar. 1996-05-10. IRAS04210+0400: Modeling the optical spectra from flaring large scale jets. https://doi.org/10.1093/mnras%2F282.4.1203

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