We present the stellar kinematics in the central 2'' of the luminous elliptical galaxy M87 (NGC 4486), using laser adaptive optics to feed the Gemini telescope integral-field spectrograph, ...Near-infrared Integral Field Spectrograph (NIFS). The velocity dispersion rises to 480 km s--1 at 02. We combine these data with extensive stellar kinematics out to large radii to derive a black hole mass equal to (6.6 ? 0.4) X 109 M , using orbit-based axisymmetric models and including only the NIFS data in the central region. Including previously reported ground-based data in the central region drops the uncertainty to 0.25 X 109 M with no change in the best-fit mass; however, we rely on the values derived from the NIFS-only data in the central region in order to limit systematic differences. The best-fit model shows a significant increase in the tangential velocity anisotropy of stars orbiting in the central region with decreasing radius, similar to that seen at the centers of other core galaxies. The black hole mass is insensitive to the inclusion of a dark halo in the models--the high angular resolution provided by the adaptive optics breaks the degeneracy between black hole mass and stellar mass-to-light ratio. The present black hole mass is in excellent agreement with the Gebhardt & Thomas value, implying that the dark halo must be included when the kinematic influence of the black hole is poorly resolved. This degeneracy implies that the black hole masses of luminous core galaxies, where this effect is important, may need to be re-evaluated. The present value exceeds the prediction of the black hole-dispersion and black hole-luminosity relations, both of which predict about 1 X 109 M for M87, by close to twice the intrinsic scatter in the relations. The high end of the black hole correlations may be poorly determined at present.
We present the first results from Bayesian AnalYsis of Multiple AGN in X-rays (BAYMAX), a tool that uses a Bayesian framework to quantitatively evaluate whether a given Chandra observation is more ...likely a single or dual point source. Although the most robust method of determining the presence of dual active galactic nuclei (AGNs) is to use X-ray observations, only sources that are widely separated relative to the instrument's point-spread function are easy to identify. It becomes increasingly difficult to distinguish dual AGNs from single AGNs when the separation is on the order of Chandra's angular resolution (<1″). Using likelihood models for single and dual point sources, BAYMAX quantitatively evaluates the likelihood of an AGN for a given source. Specifically, we present results from BAYMAX analyzing the lowest-mass dual AGN candidate to date, SDSS J0914+0853, where archival Chandra data shows a possible secondary AGN ∼ 0 3 from the primary. Analyzing a new 50 ks Chandra observation, results from BAYMAX shows that SDSS J0914+0853 is most likely a single AGN with a Bayes factor of 13.5 in favor of a single point source model. Further, posterior distributions from the dual point source model are consistent with emission from a single AGN. We find a very low probability of SDSS J0914+0853 being a dual AGN system with a flux ratio f > 0.3 and separation r > 0 3. Overall, BAYMAX will be an important tool for correctly classifying candidate dual AGNs in the literature, as well as studying the dual AGN population where past spatial resolution limits have prevented systematic analyses.
We derive improved versions of the relations between supermassive black hole mass (M BH) and host-galaxy bulge velocity dispersion ( sigma ) and luminosity (L; the M- sigma and M-L relations), based ...on 49 M BH measurements and 19 upper limits. Particular attention is paid to recovery of the intrinsic scatter (0) in both relations. We find log(M BH/M ) = alpha + beta log( sigma /200 km s-1) with ( alpha , beta , 0) = (8.12 - 0.08, 4.24 - 0.4,0.44 - 0.06) for all galaxies and ( alpha , beta , 0) = (8.23 - 0.08, 3.96 - 0.4,0.31 - 0.06) for ellipticals. The results for ellipticals are consistent with previous studies, but the intrinsic scatter recovered for spirals is significantly larger. The scatter inferred reinforces the need for its consideration when calculating local black hole mass function based on the M- sigma relation, and further implies that there may be substantial selection bias in studies of the evolution of the M- sigma relation. We estimate the M-L relationship as log(M BH/M ) = alpha + beta log(LV /1011 L ,V ) of ( alpha , beta , 0) = (8.95 - 0.11, 1.11 - 0.1,0.38 - 0.09); using only early-type galaxies. These results appear to be insensitive to a wide range of assumptions about the measurement errors and the distribution of intrinsic scatter. We show that culling the sample according to the resolution of the black hole's sphere of influence biases the relations to larger mean masses, larger slopes, and incorrect intrinsic residuals.
Abstract
We present 0.″22-resolution Atacama Large Millimeter/submillimeter Array (ALMA) observations of CO(2−1) emission from the circumnuclear gas disk in the red nugget relic galaxy PGC 11179. The ...disk shows regular rotation, with projected velocities near the center of 400 km s
−1
. We assume the CO emission originates from a dynamically cold, thin disk and fit gas-dynamical models directly to the ALMA data. In addition, we explore systematic uncertainties by testing the impacts of various model assumptions on our results. The supermassive black hole (BH) mass (
M
BH
) is measured to be
M
BH
= (1.91 ± 0.04 1
σ
statistical
−
0.51
+
0.11
systematic) × 10
9
M
⊙
, and the
H
-band stellar mass-to-light ratio
M
/
L
H
= 1.620 ± 0.004 1
σ
statistical
−
0.107
+
0.211
systematic
M
⊙
/
L
⊙
. This
M
BH
is consistent with the BH mass−stellar velocity dispersion relation but over-massive compared to the BH mass−bulge luminosity relation by a factor of 3.7. PGC 11179 is part of a sample of local compact early-type galaxies that are plausible relics of
z
∼ 2 red nuggets, and its behavior relative to the scaling relations echoes that of three relic galaxy BHs previously measured with stellar dynamics. These over-massive BHs could suggest that BHs gain most of their mass before their host galaxies do. However, our results could also be explained by greater intrinsic scatter at the high-mass end of the scaling relations, or by systematic differences in gas- and stellar-dynamical methods. Additional
M
BH
measurements in the sample, including independent cross-checks between molecular gas- and stellar-dynamical methods, will advance our understanding of the co-evolution of BHs and their host galaxies.
During the inspiral and merger of a binary black hole, gravitational radiation is emitted anisotropically due to asymmetries in the merger configuration. This anisotropic radiation leads to a ...gravitational wave kick, or recoil velocity, as large as image4000 km s super(-1). We investigate the effect gravitational recoil has on the retention of intermediate-mass black holes (IMBHs) within the population of Galactic globular clusters by simulating the response of IMBHs to black hole mergers. Assuming that our current understanding of IMBH formation is correct and yields an IMBH seed in every globular cluster, we find a significant problem in retaining low-mass IMBHs (image1000 M sub(image)) in the typical merger-rich globular cluster environment. Given a uniform black hole spin distribution and orientation and a stellar-mass black hole mass function generated in a low- metallicity system, we find that only three of the Milky Way globular clusters can retain an IMBH with an initial mass of 200 M sub(image). Even if IMBHs have an initial mass of 1000 M sub(image), only 60 would remain within Milky Way globular clusters, and each would reside only in the most massive clusters. Our calculations show that if there are black holes of mass image M sub(image) in a cluster, repeated IMBH-black hole encounters will eventually eject a image M sub(image) IMBH with greater than 30% probability. As a consequence, a large population of rogue black holes may exist in our Milky Way halo. We briefly discuss the dynamical implications of this process and its possible connection to ultraluminous X- ray sources (ULXs).
We assess the influence of massive black hole (MBH) ejections from galaxy centres due to gravitational radiation recoil, along the cosmic merger history of the MBH population. We discuss the ‘danger’ ...of recoil for MBHs as a function of different MBH spin-orbit configurations and of the host halo cosmic bias, and on how that reflects on the occupation fraction of MBHs. We assess ejection probabilities for mergers occurring in a gas-poor environment, in which the MBH binary coalescence is driven by stellar dynamical processes and the spin-orbit configuration is expected to be isotropically distributed. We contrast this case with the ‘aligned’ case. The latter is the more realistic situation for gas-rich, i.e. ‘wet’, mergers, which are expected for high-redshift galaxies. We find that if all haloes at z > 5–7 host an MBH, the probability of the Milky Way (or similar size galaxy) to host an MBH today is less than 50 per cent, unless MBHs form continuously in galaxies. The occupation fraction of MBHs, intimately related to halo bias and MBH formation efficiency, plays a crucial role in increasing the retention fraction. Small haloes, with shallow potential wells and low escape velocities, have a high ejection probability, but the MBH merger rate is very low along their galaxy formation merger hierarchy: MBH formation processes are likely inefficient in such shallow potential wells. Recoils can decrease the overall frequency of MBHs in small galaxies to ∼60 per cent, while they have little effect on the frequency of MBHs in large galaxies (at most a 20 per cent effect).
Abstract We present the first results from the Revealing Low-Luminosity Active Galactic Nuclei (ReveaLLAGN) survey, a JWST survey of seven nearby LLAGNs. We focus on two observations with the ...Mid-Infrared Instrument (MIRI)’s Medium-Resolution Spectrometer of the nuclei of NGC 1052 and Sombrero (NGC 4594/M104). We also compare these data to public JWST data of higher-luminosity AGNs, NGC 7319 and NGC 7469. JWST clearly separates the AGN spectrum from the galaxy light even in Sombrero, the faintest target in our survey; the AGN components have very red spectra. We find that the emission-line widths in both NGC 1052 and Sombrero increase with increasing ionization potential, with FWHM > 1000 km s −1 for lines with ionization potential ≳ 50 eV. These lines are also significantly blueshifted in both LLAGNs. The high-ionization-potential lines in NGC 7319 show neither broad widths nor significant blueshifts. Many of the lower-ionization-potential emission lines in Sombrero show significant blue wings extending >1000 km s −1 . These features and the emission-line maps in both galaxies are consistent with outflows along the jet direction. Sombrero has the lowest-luminosity high-ionization-potential lines (Ne v and O iv ) ever measured in the mid-infrared, but the relative strengths of these lines are consistent with higher-luminosity AGNs. On the other hand, the Ne v emission is much weaker relative to the Ne iii and Ne ii lines of higher-luminosity AGNs. These initial results show the great promise that JWST holds for identifying and studying the physical nature of LLAGNs.
The prevalence and properties of kiloparsec-scale outflows in nearby Type 1 quasars have been the subject of little previous attention. This work presents Gemini integral field spectroscopy of 10 ...Type 1 radio-quiet quasars at . The excellent image quality, coupled with a new technique to remove the point-spread function using spectral information, allows the fitting of the underlying host on a spaxel-by-spaxel basis. Fits to stars, line-emitting gas, and interstellar absorption show that 100% of the sample hosts warm ionized and/or cool neutral outflows with spatially averaged velocities ( ) of 200-1300 and peak velocities (maximum ) of 500-2600 . These minor-axis outflows are powered primarily by the central active galactic nucleus, reach scales of 3-12 kpc, and often fill the field of view. Including molecular data and Type 2 quasar measurements, nearby quasars show a wide range in mass outflow rates ( to ) and momentum boosts . After extending the mass scale to Seyferts, dM/dt and dE/dt correlate with black hole mass ( and ). Thus, the most massive black holes in the local universe power the most massive and energetic quasar-mode winds.
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