Ionized outflows in luminous type 2 AGNs at z < 0.6: no evidence for significant impact on the host galaxies

Montse Villar-Martin, Santiago Arribas, Bjorn Emonts, Andrew Humphrey, Clive Tadhunter, Patricia Bessiere, Antonio Cabrera Lavers, Cristina Ramos Almeida. 2016. Ionized outflows in luminous type 2 AGNs at z<0.6: no evidence for significant impact on the host galaxies. Monthly Notices of the Royal Astronomical Society, 460, 1, 130-162, DOI: 10.1093/mnras/stw901

We investigate the presence of extended ionized outflows in 18 luminous type 2 AGNs (11 quasars and 7 high-luminosity Seyfert 2s) at 0.3< z< 0.6 based on VLT-FORS2 spectroscopy. We infer typical lower limits on the radial sizes of the outflows R-o greater than or similar to several x 100 pc and upper limits R-o less than or similar to 1-2 kpc. Our results are inconsistent with related studies which suggest that large scale (R-o similar to several-15 kpc) are ubiquitous in QSO2. We study the possible causes of discrepancy and propose that seeing smearing is the cause of the large inferred sizes. The implications in our understanding of the feedback phenomenon are important since the mass M-o (through the density), mass injection. M o and energy injection. (E) over dot(o) rates of the outflows become highly uncertain. One conclusion seems unavoidable: M-o, (M) over dot(o) and (E) over dot(o) are modest or low compared with previous estimations. We obtain typically M-o less than or similar to (0.4-22) x 10(6) M-circle dot (median 1.1 x 10(6) M-circle dot) assuming n = 1000 cm(-3). These are similar to 10(2)-10(4) times lower than values reported in the literature. Even under themost favourable assumptions, we obtain (M) over dot(o) less than or similar to 10 M-circle dot yr(-1) in general, 100-1000 times lower than claimed in related studies. Although the uncertainties are large, it is probable that these are lower than typical star-forming rates. In conclusion, no evidence is found supporting that typical outflows can affect the interstellar medium of the host galaxies across spatial scales greater than or similar to 1-2 kpc.

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