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Powerful ionized gas outflows in the interacting radio galaxy 4C +29.30

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 نشر من قبل Guilherme S. Couto
 تاريخ النشر 2020
  مجال البحث فيزياء
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We investigate the ionized gas excitation and kinematics in the inner $4.3 times 6.2$ kpc$^{2}$ of the merger radio galaxy 4C +29.30. Using optical integral field spectroscopy with the Gemini North Telescope, we present flux distributions, line-ratio maps, peak velocities and velocity dispersion maps as well as channel maps with a spatial resolution of $approx 955$ pc. We observe high blueshifts of up to $sim -650$ km s$^{-1}$, in a region $sim 1$ south of the nucleus (the southern knot, SK), which also presents high velocity dispersions ($sim 250$ km s$^{-1}$), which we attribute to an outflow. A possible redshifted counterpart is observed north from the nucleus (the northern knot, NK). We propose that these regions correspond to a bipolar outflow possibly due to the interaction of the radio jet with the ambient gas. We estimate a total ionized gas mass outflow rate of $dot{M}_{out} = 25.4 substack{+11.5 -7.5}$ M$_odot$ yr$^{-1}$ with a kinetic power of $dot{E} = 8.1 substack{+10.7 -4.0} times 10^{42}$ erg s$^{-1}$, which represents $5.8 substack{+7.6 -2.9} %$ of the AGN bolometric luminosity. These values are higher than usually observed in nearby active galaxies with the same bolometric luminosities and could imply a significant impact of the outflows in the evolution of the host galaxy. The excitation is higher in the NK (that correlates with extended X-ray emission, indicating the presence of hotter gas) than in the SK, supporting a scenario in which an obscuring dust lane is blocking part of the AGN radiation to reach the southern region of the galaxy.



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