Radio sources in low-luminosity active galactic nuclei IV. Radio luminosity function, importance of jet power, and radio properties of the complete Palomar sample

By N. Nagar, Heino Falcke, A. S. Wilson. 2005

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We present the completed results of a high resolution radio imaging survey of all (∼200) low-luminosity active galactic nuclei (LLAGNs) and AGNs in the Palomar Spectroscopic Sample of all (∼488) bright northern galaxies. The high incidences of pc-scale radio nuclei, with implied brightness temperatures >10 7 K, and sub-parsec jets argue for accreting black holes in >50% of all LINERs and low-luminosity Seyferts; there is no evidence against all LLAGNs being mini-AGNs. The detected parsec-scale radio nuclei are preferentially found in massive ellipticals and in type 1 nuclei (i.e. nuclei with broad Hα emission). The radio luminosity function (RLF) of Palomar Sample LLAGNs and AGNs extends three orders of magnitude below, and is continuous with, that of "classical" AGNs. We find marginal evidence for a low-luminosity turnover in the RLF; nevertheless LLAGNs are responsible for a significant fraction of present day mass accretion. Adopting a model of a relativistic jet from Falcke & Biermann, we show that the accretion power output in LLAGNs is dominated by the kinetic power in the observed jets rather than the radiated bolometric luminosity. The Palomar LLAGNs and AGNs follow the same scaling between jet kinetic power and narrow line region (NLR) luminosity as the parsec to kilo-parsec jets in powerful radio galaxies. Eddington ratios lEdd (=LEmitted/LEddington )o f≤10 −1 −10 −5 are implied in jet models of the radio emission. We find evidence that, in analogy to Galactic black hole candidates, LINERs are in a "low/hard" state (gas poor nuclei, low Eddington ratio, ability to launch collimated jets) while low-luminosity Seyferts are in a "high" state (gas rich nuclei, higher Eddington ratio, less likely to launch collimated jets). In addition to dominating the radiated bolometric luminosity of the nucleus, the radio jets are energetically more significant than supernovae in the host galaxies, and are potentially able to deposit sufficient energy into the innermost parsecs to significantly slow the gas supply to the accretion disk.

Subfields: Astronomy and Astrophysics, Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/244adb3f4e87be66e3dc982171b66972ddb7955d

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Citations in the corpus

Observational evidence for intermediate-mass black holes (2017, background): “…and from the finding of a hard X-ray core cLow-ionization nuclear emission line region (LINERs) are associated with low-luminosity AGN (e.g., Nagar et al. 2005; Mezcua & Prieto 2014) (Binder et al. 2011), UV variability (Maoz et al. 2005), unresolved and variable hot dust emission (Seth et…”
Measuring the kinetic power of active galactic nuclei in the radio mode (2007, unknown): “…(1) Sambruna et al. (1999); (2) Young et al. (2002); (3) Tadhunter et al. (2003); (4) Rafferty et al. (2006); (5) Carilli & Barthel (1996); (6) Nagar et al. (2005); (6) De Ruiter et al. (1986); (7) Pellegrini (2005b); (8) Allen et al. (2006); (9) Allen et al. (2001); (10) Fabian et al.…”
Radio Loudness of Active Galactic Nuclei: Observational Facts and Theoretical Implications (2006, unknown): “…radio loudness,R, on the Eddington ratio, k, assuming k ¼ Lbol /LEdd ¼ 10(LB /LEdd) (see, e.g., Richards et al. 2006).7 Our results confirm the trend of the increase of radio loudness with decreasing Eddington ratio, originally noticed by Ho (2002; see also Merloni et al. 2003; Nagar et al. 2005).”
Outflows in Active Galactic Nucleus/Starburst-Composite Ultraluminous Infrared Galaxies (2005, background): “They typically possess outflows in the form of spatially resolved jets on parsec to kiloparsec scales, in both radioloud (e.g., Zensus 1997;Worrall &Birkinshaw 2004) and radioquiet (e.g., Morganti et al. 1999; Nagar et al. 2005) objects.”
AGN heating and ICM cooling in the HIFLUGCS sample of galaxy clusters (2008, methodology): “In order to check for such an occurrence, we simulated randomized radio and X-ray luminosities confined to the observed ranges following the distributions, n(LX)dLX ∝ L−0.7X (Böhringer et al. 2002) and n(LR)dLR ∝ L−0.78R (Nagar et al. 2005), where n is the source number density.”
Refining the fundamental plane of accreting black holes (2006, background): “In the KFC sample we only consider the non-Seyfert galaxies in the Nagar et al. (2005) sample; the Seyferts of this sample will be discussed separately as, even though they are of low luminosity, they still may belong to the supermassive analog of high state XRBs, because their black hole masses…”
A synthesis model for AGN evolution: supermassive black holes growth and feedback modes (2008, methodology): “For example, Nagar et al. (2005) and Filho et al. (2006) have used high-resolutionradio imaging of a magnitude limited sample of bright nearby galaxies (the Palomar sample) to show that at least a quarter (and possibly as much as half) of them are true AGN, albeit of very low luminosity.”
THE NGC 404 NUCLEUS: STAR CLUSTER AND POSSIBLE INTERMEDIATE-MASS BLACK HOLE (2010, background): “…M/LI = 1.28 from §5.4, (f) del Ŕıo et al. (2004), (g) Wiklind & Henkel (1990), corrected to D = 3.06 Mpc, (h) heliocentric velocity, see §4.1. with the VLA in A array (Nagar et al. 2005), however, del Rı́o et al. (2004) do detect an unresolved 3 mJy continuum source at 1.4 GHz using the C array.”
Accretion states and radio loudness in active galactic nuclei: analogies with X-ray binaries (2006, methodology): “For the radio luminosity function we use βR = 0.78 (Nagar et al. 2005), for the X-rays βX = 2.34 (Ueda et al. 2003) and for the optical luminosity function βO = 2.95 (Richards et al. 2006).”
The Coincidence of Nuclear Star Clusters and Active Galactic Nuclei (2008, background): “Such radio sources are detected in about a third of galaxies classified as composite or AGN objects in the Palomar survey (Nagar et al. 2005).”