Observation Of Radiation Driven Outflows From Lergs And Their Potential Role In Agn Feedback

Low excitation radio galaxies (LERGs) are weakly accreting active galactic nuclei (AGN) believed to be fuelled by radiatively inefficient accretion processes. Recently, studies have found evidence for gas outflows in these galaxies, suspected to be driven by the AGN jets. To investigate the mechanisms responsible for such outflows, we select 802 LERGs using the Best & Heckman (2012) catalogue of radio galaxies at z < 0.3. We detect ionized outflows in 1.5% of LERGs based on modelling the [O III] (5007A) emission line complex. The black hole accretion rates in LERGs with outflows are found to be close to 1% of the Eddington limit, and thus represent the high end of the LERG accretion rate distribution. Strikingly, we find no correlation of these outflows with their jet powers, which could indicate that these outflows are driven by the radiation pressure from the AGN accretion disk. We report a SFR of of 1-12 M_☉ /yr. Moreover, we observe higher mass outflow rates (7-150 M_☉/yr) for these LERGs than the luminous quasars for a given bolometric luminosity, which could be possibly due to the radio source in LERGs, boosting the mass-loading. This scenario could indicate that these outflows could potentially drive feedback in LERGs.