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Register a new userOutflows, Inflows and Young Stars in the inner 200 pc of the Seyfert galaxy NGC 2110
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Added by
Rogemar Andre Riffel
Publication date
2019
fields
Physics
and research's language is
English
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We present a two-dimensional mapping of stellar population age components, emission-line fluxes, gas excitation and kinematics within the inner $sim200$ pc of the Seyfert 2 galaxy NGC 2110. We used the Gemini North Integral Field Spectrograph (NIFS) in the J and K bands at a spatial resolution of $sim22$ pc. The unresolved nuclear continuum is originated in combined contributions of young stellar population (SP; age$leq100$ Myr), a featureless AGN continuum and hot dust emission. The young-intermediate SP ($100<$age$leq700$ Myr) is distributed in a ring-shaped structure at $approx140$ pc from the nucleus, which is roughly coincident with the lowest values of the stellar velocity dispersion. In the inner $approx115$ pc the old SP (age$>2$ Gyr) is dominant. The [FeII]1.25$mu$m emission-line flux distribution is correlated with the radio emission and its kinematics comprise two components, one from gas rotating in the galaxy plane and another from gas in outflow within a bicone oriented along north-south. These outflows seem to originate in the interaction of the radio jet with the ambient gas producing shocks that are the main excitation mechanism of the [FeII] emission. We estimate: (1) an ionized gas mass outflow rate of $sim0.5$ M$_odot$/yr at $sim$70 pc from the nucleus; and (2) a kinetic power for the outflow of only 0.05% of the AGN bolometric luminosity implying weak feedback effect on the galaxy.
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