Dynamical models of NGC 3115

Observations of nearby galaxies reveal a strong correlation between the mass of the central dark object M BH and the velocity dispersion of the host galaxy, of the form logðM BH =M Þ ¼ þ logð = 0 Þ; however, published estimates of the slope span a wide range (3.75-5.3). Merritt & Ferrarese have argued that low slopes (d4) arise because of neglect of random measurement errors in the dispersions and an incorrect choice for the dispersion of the Milky Way Galaxy. We show that these explanations and several others account for at most a small part of the slope range. Instead, the range of slopes arises mostly because of systematic differences in the velocity dispersions used by different groups for the same galaxies. The origin of these differences remains unclear, but we suggest that one significant component of the difference results from Ferrarese & Merritt's extrapolation of central velocity dispersions to r e =8 (r e is the effective radius) using an empirical formula. Another component may arise from dispersion-dependent systematic errors in the measurements. A new determination of the slope using 31 galaxies yields ¼ 4:02 AE 0:32, ¼ 8:13 AE 0:06 for 0 ¼ 200 km s À1 . The M BH -relation has an intrinsic dispersion in log M BH that is no larger than 0.25-0.3 dex and may be smaller if observational errors have been underestimated. In an appendix, we present a simple kinematic model for the velocity-dispersion profile of the Galactic bulge.

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“…6). See also Emsellem, Dejonghe, & Bacon (1999) NGC 3245.-The velocity dispersion is obtained from Simien & Prugniel (1998).…”

Section: Comments On Individual Galaxiesmentioning

confidence: 99%

The Slope of the Black Hole Mass versus Velocity Dispersion Correlation

Tremaine

Gebhardt

Bender³

et al. 2002

ApJ

2,484

166

3,186

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“…Those were parametrized using Multi-Gaussian Expansions (MGE; Emsellem et al 1994;Cappellari 2002) and were taken from various studies (Emsellem et al 1999;Cappellari et al 2006;Scott et al 2009Scott et al , 2013C+15). Here, we use the same characterizations of the distributions of stars within the galaxies.…”

Section: Sample Data and Dynamical Modellingmentioning

confidence: 99%

The mass discrepancy acceleration relation in early-type galaxies: extended mass profiles and the phantom menace to MOND

Janz

Cappellari

Romanowsky

et al. 2016

Mon. Not. R. Astron. Soc.

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The dark matter (DM) haloes around spiral galaxies appear to conspire with their baryonic content: empirically, significant amounts of DM are inferred only below a universal characteristic acceleration scale. Moreover, the discrepancy between the baryonic and dynamical mass, which is usually interpreted as the presence of DM, follows a very tight mass discrepancy acceleration (MDA) relation. Its universality, and its tightness in spiral galaxies, poses a challenge for the DM interpretation and was used to argue in favour of MOdified Newtonian Dynamics (MOND). Here, we test whether or not this applies to early-type galaxies. We use the dynamical models of fast-rotator early-type galaxies by Cappellari et al. based on ATLAS 3D and SLUGGS data, which was the first homogenous study of this kind, reaching ∼4R e , where DM begins to dominate the total mass budget. We find the early-type galaxies to follow an MDA relation similar to spiral galaxies, but systematically offset. Also, while the slopes of the mass density profiles inferred from galaxy dynamics show consistency with those expected from their stellar content assuming MOND, some profiles of individual galaxies show discrepancies.

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“…Figure 4 shows the relation between sub-parsec radio luminosity, M BH , and host galaxy bulge luminosity in the B-band. Black hole masses are either directly measured from stellar, gas, or maser dynamics, or estimated from the central stellar velocity dispersion, σ c (Emsellem et al 1999;Gebhardt et al 2003, for all other references see Nagar et al 2002a). We used the relationship of Tremaine et al (2002) to estimate M BH from σ c .…”

Section: Radio Luminosity and Black Hole Massmentioning

confidence: 99%

Radio sources in low-luminosity active galactic nuclei

Nagar¹,

Falcke²,

Wilson³

2005

A&A

308

482

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Abstract. 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 l Edd (=L Emitted /L Eddington ) of ≤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.

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Dynamical models of NGC 3115

Cited by 109 publications

References 39 publications

The Slope of the Black Hole Mass versus Velocity Dispersion Correlation

The Slope of the Black Hole Mass versus Velocity Dispersion Correlation

The mass discrepancy acceleration relation in early-type galaxies: extended mass profiles and the phantom menace to MOND

Radio sources in low-luminosity active galactic nuclei

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