A Direct Linkage Between Agn Outflows in the Narrow-Line Regions and the X-Ray Emission From the Accretion Disks

Abstract

The origin of outflow in narrow-line region (NLR) of active galactic nucleus (AGN) is studied in this paper by focusing on the relationship between the [O III]λ5007 line profile and the hard X-ray (in a bandpass of 2-10 keV) emission from the central SMBH in type-I AGNs. A sample of 47 local X-ray selected type-I AGNs at z < 0.2 is extracted from the 2XMMi/SDSS DR7 catalog that is originally crossmatched by Pineau et al. The X-ray luminosities in an energy band from 2 to 10keV of these luminous AGNs range from 10 42 to 10 44 erg s −1 . A joint spectral analysis is performed on their optical and X-ray spectra, in which the [O III] line profile is modeled by a sum of several Gaussian functions to quantify its deviation from a pure Gaussian function. The statistics allows us to identify a moderate correlation with a significance level of 2.78σ: luminous AGNs with stronger [O III] blue asymmetry tend to have steeper hard X-ray spectra. By identifying a role of L/L Edd on the correlation at a 2 − 3σ significance level in both direct and indirect ways, we argue that the photon index versus asymmetry correlation provides evidence that the AGN's outflow commonly observed in its NLR is related with the accretion process occurring around the central SMBH, which favors the wind/radiation model for the origin of the outflow in luminous AGNs.Subject headings: galaxies: nuclei -quasars: emission lines -X-ray: galaxies optical spectroscopic sample. Different results are, however, obtained by various authors. On the one hand, there is ample evidence that the [O III] line blue asymmetry and bulk velocity blueshift are strongly correlated with Eddington ratio (L/L Edd , where L Edd = 1.26× 10 38 (M BH /M ⊙ ) erg s −1 is the Eddington luminosity) of the central AGNs: higher the L/L Edd , stronger the blue asymmetry and larger the bulk velocity blueshift will be (e.g., Zhang et al. 2011;Wang et al. 2011;Wang 2015;Boroson 2005;Bian et al. 2005). In addition, the extreme "blue outliers" usually defined as the objects with [O III] bulk blueshift larger than 250km s −1 (e.g., Zamanov et al. 2002;Zhou et al. 2006;Komossa et al. 2008) are found to exclusively occur in the AGNs associated with high L/L Edd . On the other hand, the relation between the [O III] line profile and radio emission has been reported in the previous studies. Early studies show that the [O III] line width is found to be correlated with radio luminosity at 1.4 GHz (L 1.4GHz ) for a sample of flat-spectrum radio galaxies (e.g., Heckman et al. 1984;Whittle 1985). Mullaney et al. (2013) and Zakamska & Greene (2014) recently analyzed the [O III] line profile in a large sample of both type I and type II AGNs detected by the SDSS spectroscopic survey. Their results suggest that the [O III] line width is more strongly related to L 1.4GHz than the other AGNs parameters (e.g., line luminosity and L/L Edd ).The origin of feedback in local type I AGNs is studied in this paper by focusing on the relationship between the outflow traced by the [O III] line profile and the X-ray em...

Properties of the Narrow Line Seyfert 1 Galaxies Revisited

“…Assuming a continuity of scaling as n e ∝ r −2 , some of the NLS1s in Xu et al (2012) have much lower NLR density than that in BLS1s, and they could have less gamma-ray opacity. In addition, it is found that some 'blue outliers' occur in the NLS1 galaxies with a fraction of 5-16% (depending on the [O III] blue wing's velocity from 250 to 150 km/s by definition), but not found in the BLS1s (Komossa et al 2008), suggesting that the outflows could be seen more often in the poleon NLS1s than in the BLS1s, but the physical outflow in the NLR should be driven mainly by the accretion rate (Wang et al 2016).…”

Does Feedback from Supermassive Black Holes Coevolve with the Host in Type 2 Quasars?

“…On the observational ground, the feedback is usually traced by the frequently observed outflows from central SMBHs in order to study not only its origin but also its effect on host galaxies (see reviews in Veilleux & Rupke 2005;Fabian 2012). Among the different diagnoses of the outflows, the most used is the blue asymmetry of the prominent [O III]λλ4959,5007 doublet and its bulk blueshift with respect to the local system, which is found to be quite prevalent in both local and distant active galactic nuclei (AGNs; e.g., Heckman et al 1981;Véron-Cetty et al 2001;Zamanov et al 2002;Marziani et al 2003;Aoki et al 2005;Boroson 2005;Komossa et al 2008;Xu & Komossa 2009;Villar-Martín et al 2011;Liu et al 2013;Mullaney et al 2013;Zhang et al 2013;Harrison et al 2014;Villar Martín et al 2014;Karouzos et al 2016;Wang et al 2016Wang et al , 2018.…”