Narrow-line region gas kinematics of 24 264 optically selected AGN: the radio connection

Abstract

Using a sample of 24264 optically selected AGNs from the SDSS DR7 database, we characterise how the profile of the [O III]λ5007 emission line relates to bolometric luminosity (L AGN ), Eddington ratio, radio loudness, radio luminosity (L 1.4 GHz ) and optical class (i.e., broad/narrow line Seyfert 1, Type 2) to determine what drives the kinematics of this kpcscale line emitting gas. Firstly, we use spectral stacking to characterise how the average [O III]λ5007 profile changes as function of these five variables. After accounting for the known correlation between L AGN and L 1.4 GHz , we report that L 1.4 GHz has the strongest influence on the [O III]λ5007 profile, with AGNs of moderate radio luminosity (L 1.4 GHz = 10 23 − 10 25 W Hz −1 ) having the broadest [O III]λ5007 profiles. Conversely, we find only a modest change in the [O III]λ5007 profile with increasing radio loudness and find no significant difference between the [O III]λ5007 profiles of broad and narrow-line Seyfert 1s. Similarly, only the very highest Eddington ratio AGNs (i.e., > 0.3) show any signs of having broadened [O III]λ5007 profiles, although the small numbers of such extreme AGNs in our sample mean we cannot rule out that other processes (e.g., radio jets) are responsible for this broadening. The [O III]λ5007 profiles of Type 1 and Type 2 AGNs show the same trends in terms of line width, but Type 1 AGNs display a much stronger "blue-wing", which we interpret as evidence of outflowing ionised gas. We perform multi-component fitting to the Hβ, [O III]λλ4959, 5007, [N II]λλ6548, 6584 and Hα lines for all the AGNs in our sample to calculate the proportions of AGNs with broad [O III]λ5007 profiles. The individual fits confirm the results from our stacked spectra; AGNs with L 1.4 GHz > 10 23 W Hz −1 are roughly 5 times more likely to have extremely broad [O III]λ5007 lines (FWHM Avg > 1000 km s −1 ) compared to lower L 1.4 GHz AGNs and the width of the [O III]λ5007 line peaks in moderate radio luminosity AGNs (L 1.4 GHz ∼ 10 24 W Hz −1 ). Our results are consistent with the most disturbed gas kinematics being induced by compact radio cores (rather than powerful radio jets), although broadened [O III]λ5007 lines are also present, but much rarer, in low L 1.4 GHz systems. Our catalogue of multi-component fits is freely available as an online resource for statistical studies of the kinematics and luminosities of the narrow and broad line AGN regions and the identification of potential targets for follow-up observations.

X-shooter reveals powerful outflows in z ∼ 1.5 X-ray selected obscured quasi-stellar objects

“…We found that the objects for which we detect a broad component have FWHM larger than the average value observed in SDSS Type 2 AGN samples at similar observed [OIII] luminosity (Mullaney et al 2013;Greene et al 2011, see pinkish-grey and green points in Fig. 7).…”

“…Mullaney et al (2013) presented the analysis from a multicomponent (allowing for the presence of a broad component) line fit of the [OIII]5007 line in the SDSS population. In the lower panel of Fig.…”

STORM IN A “TEACUP”: A RADIO-QUIET QUASAR WITH ≈10 kpc RADIO-EMITTING BUBBLES AND EXTREME GAS KINEMATICS

“…Our observations of the "Teacup" AGN shed some light on the observed correlation between radio luminosity and the ionized gas kinematics (i.e., outflow velocities) seen in radio-quiet AGN (Mullaney et al 2013;). The radio emission in this radio-quiet AGN is tracing both a ≈1 kpc highvelocity outflow and ≈10-12 kpc radio bubbles that are likely to both be AGN driven.…”

“…Using the Sloan Digital Sky Survey (SDSS) spectrum, Reyes et al (2008) and Mullaney et al (2013) independently identified this source as a type 2 ("obscured") AGN.…”

Evidence of ongoing AGN-driven feedback in a quiescent post-starburst E+A galaxy

“…On the other hand, there is plenty of evidence for massive outflows in ULIRGs (e.g., Rupke, Veilleux & Sanders 2002;Martin 2005Martin , 2006) but these are not connected directly with the post starburst phase of such systems. Obviously, there are thousands of AGNs that show some indication of outflow, such as the large SDSS type-II sample studied by Mullaney et al (2013) and the more detailed study of 16 of those by Harrison et al (2014). However, there is no direct link between these outflows and the specific evolutionary phase of E+A galaxies.…”