M. Villar Martín, S. Arribas, B. H. C. Emonts, A. Humphrey, C. N. Tadhunter, P. S. Bessiere, A. Cabrera Lavers, C. Ramos Almeida

Abstract
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 ≳ several × 100 pc and upper limits R_o ≲ 1-2 kpc. Our results are inconsistent with related studies which suggest that large scale (R_o ~ 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 dot{M}_o and energy injection Ė_o rates of the outflows become highly uncertain. One conclusion seems unavoidable: M_o, skew3dot{M}_o and Ė_o are modest or low compared with previous estimations. We obtain typically M_o ≲ (0.4-22) × 10⁶ M_☉ (median 1.1 × 10⁶ M_☉) assuming n = 1000 cm^-3. These are ~10²-10⁴ times lower than values reported in the literature. Even under the most favourable assumptions, we obtain dot{M}_o ≲ 10 M_☉ 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 ≳ 1-2 kpc.

Keywords
galaxies: active, galaxies: evolution, quasars: emission lines, quasars: general

Monthly Notices of the Royal Astronomical Society
Volume 460, Issue 1, Page 130
2016 July

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