79 results on '"Sphere of influence (black hole)"'
Search Results
2. Lydian Sardis and Its Sphere of Influence in the Light of Laboratory Analysis Results
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Vasilica Lungu and Pierre Dupont
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Archeology ,History ,Classical mechanics ,Sphere of influence (black hole) ,media_common.quotation_subject ,Art ,Classics ,media_common - Abstract
Alongside its programme of chemical analyses of Archaic East Greek pottery, the Lyon Laboratory for Archaeometry has also looked into the field of Anatolian wares, first of all through additional samples from Lydian Sardis and from Kelainai, as well as with a small collection from Daskyleion. The results obtained enriched our data bank of valuable references on these sites and led to useful comparisons with the Greek settlements of Old Smyrna and Ephesus, both in close relationships with the Lydian sphere.
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- 2020
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3. Plasma Waves in the Distant Martian Environment: Implications for Mars' Sphere of Influence
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Katja Klein, Joe Giacalone, J. R. Gruesbeck, Jared Espley, and T. M. Esman
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Physics ,Martian ,Geophysics ,Sphere of influence (black hole) ,Whistler ,Space and Planetary Science ,Mars Exploration Program ,Plasma ,Magnetic field ,Exosphere ,Astrobiology - Published
- 2021
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4. Stravinsky’s Sphere of Influence: Paris and Beyond
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Inessa Bazayev
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Classical mechanics ,Sphere of influence (black hole) ,Philosophy - Published
- 2020
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5. Opne Access: A legitimate sphere of influence: Understanding France’s turn to multilateralism in Africa
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Stefano Recchia
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Sphere of influence (black hole) ,Political science ,Political economy ,Multilateralism - Published
- 2020
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6. Competition between India and China for Domain, Connectivity and Sphere of Influence
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Suksoo Kim
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Competition (economics) ,Embryology ,Sphere of influence (black hole) ,Economics ,Cell Biology ,Statistical physics ,Anatomy ,China ,Developmental Biology ,Domain (software engineering) - Published
- 2018
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7. The imprints of AGN feedback within a supermassive black hole's sphere of influence
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Christopher S. Reynolds, A. C. Fabian, Paul Nulsen, Joanna M Piotrowska, Jon M. Miller, Helen Russell, Brian R. McNamara, Piotrowska-Karpov, Joanna [0000-0003-1661-2338], Reynolds, Christopher [0000-0002-1510-4860], and Apollo - University of Cambridge Repository
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Angular momentum ,Sphere of influence (black hole) ,Radiative cooling ,Bondi accretion ,Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Cooling flow ,7. Clean energy ,01 natural sciences ,0103 physical sciences ,galaxies: clusters: M87 ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,High Energy Astrophysical Phenomena (astro-ph.HE) ,Physics ,Supermassive black hole ,Jet (fluid) ,010308 nuclear & particles physics ,Astronomy and Astrophysics ,Radius ,Astrophysics - Astrophysics of Galaxies ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,X-rays: galaxies: clusters ,intergalactic medium ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics - High Energy Astrophysical Phenomena - Abstract
We present a new 300 ks Chandra observation of M87 that limits pileup to only a few per cent of photon events and maps the hot gas properties closer to the nucleus than has previously been possible. Within the supermassive black hole's gravitational sphere of influence, the hot gas is multiphase and spans temperatures from 0.2 to 1 keV. The radiative cooling time of the lowest temperature gas drops to only 0.1-0.5 Myr, which is comparable to its free fall time. Whilst the temperature structure is remarkably symmetric about the nucleus, the density gradient is steep in sectors to the N and S, with $\rho{\propto}r^{-1.5\pm0.1}$, and significantly shallower along the jet axis to the E, where $\rho{\propto}r^{-0.93\pm0.07}$. The density structure within the Bondi radius is therefore consistent with steady inflows perpendicular to the jet axis and an outflow directed E along the jet axis. By putting limits on the radial flow speed, we rule out Bondi accretion on the scale resolved at the Bondi radius. We show that deprojected spectra extracted within the Bondi radius can be equivalently fit with only a single cooling flow model, where gas cools from 1.5 keV down below 0.1 keV at a rate of 0.03 M$_{\odot}$/yr. For the alternative multi-temperature spectral fits, the emission measures for each temperature component are also consistent with a cooling flow model. The lowest temperature and most rapidly cooling gas in M87 is therefore located at the smallest radii at ~100 pc and may form a mini cooling flow. If this cooling gas has some angular momentum, it will feed into the cold gas disk around the nucleus, which has a radius of ~80 pc and therefore lies just inside the observed transition in the hot gas structure., Comment: 18 pages, 11 figures, 3 tables, accepted to MNRAS
- Published
- 2018
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8. США как мировой лидер: реалии, теории, перспективы
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Physics ,Sphere of influence (black hole) ,Classical mechanics - Published
- 2018
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9. A Catalog of Host Galaxies for WISE-selected AGN: Connecting Host Properties with Nuclear Activity and Identifying Contaminants
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Daniel Stern, Roberto J. Assef, R. Scott Barrows, and Julia M. Comerford
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Physics ,Supermassive black hole ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,Active galactic nucleus ,Sphere of influence (black hole) ,Star formation ,Astrophysics::High Energy Astrophysical Phenomena ,Continuum (design consultancy) ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Redshift ,Galaxy ,Luminosity ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics::Galaxy Astrophysics ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We present a catalog of physical properties for galaxies hosting active galactic nuclei (AGN) detected by the Wide-field Infrared Survey Explorer (WISE). By fitting broadband spectral energy distributions of sources in the WISE AGN Catalog (Assef et al. 2018) with empirical galaxy and AGN templates, we derive photometric redshifts, AGN bolometric luminosities, measures of AGN obscuration, host galaxy stellar masses, and host galaxy star formation rates (SFRs) for 695,273 WISE AGN. The wide-area nature of this catalog significantly augments the known number of obscured AGN out to redshifts of z~3 and will be useful for studies focused on AGN or their host galaxy physical properties. We first show that the most likely non-AGN contaminants are galaxies at redshifts of z=0.2-0.3, with relatively blue W1-W2 colors, and with high specific SFRs for which the dust continuum emission is elevated in the W2 filter. Toward increasingly lower redshifts, WISE AGN host galaxies have systematically lower specific SFRs, relative to those of normal star forming galaxies, likely due to decreased cold gas fractions and the time delay between global star formation and AGN triggering. Finally, WISE AGN obscuration is not strongly correlated with AGN bolometric luminosity but shows a significant negative correlation with Eddington ratio. This result is consistent with a version of the `receding torus' model in which the obscuring material is located within the supermassive black hole gravitational sphere of influence and the dust inner radius increases due to radiation pressure., 21 pages, 17 figures. Accepted for publication in the Astrophysical Journal. The full catalog is available from the publisher or from the corresponding author upon request
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- 2021
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10. Reich, Sphere of Influence, Great Power
- Author
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Reinhard Höhn
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Physics ,Great power ,Sphere of influence (black hole) ,Classical mechanics - Published
- 2019
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11. The rate of stellar mass black hole scattering in galactic nuclei
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Bence Kocsis and Alexander Rasskazov
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High Energy Astrophysical Phenomena (astro-ph.HE) ,Physics ,Sphere of influence (black hole) ,Number density ,010504 meteorology & atmospheric sciences ,Stellar mass ,Center (category theory) ,FOS: Physical sciences ,Astronomy and Astrophysics ,General Relativity and Quantum Cosmology (gr-qc) ,Astrophysics ,01 natural sciences ,LIGO ,Galaxy ,General Relativity and Quantum Cosmology ,Black hole ,Stars ,13. Climate action ,Space and Planetary Science ,0103 physical sciences ,Astrophysics - High Energy Astrophysical Phenomena ,010303 astronomy & astrophysics ,0105 earth and related environmental sciences - Abstract
We consider a black hole (BH) density cusp in a nuclear star cluster (NSC) hosting a supermassive back hole (SMBH) at its center. Assuming the stars and BHs inside the SMBH sphere of influence are mass-segregated, we calculate the number of BHs that sink into this region under the influence of dynamical friction. We find that the total number of BHs increases significantly in this region due to this process for lower mass SMBHs by up to a factor of 5, but there is no increase in the vicinity of the highest mass SMBHs. Due to the high BH number density in the NSC, BH-BH binaries form during close approaches due to GW emission. We update the previous estimate of O'Leary et al. for the rate of such GW capture events by estimating the $\langle n^2\rangle/\langle n\rangle^2$ parameter where $n$ is the number density. We find a BH merger rate for this channel to be in the range $\sim0.01-0.1 \, \mathrm{Gpc^{-3}yr^{-1}}$. The total merger rate is dominated by the smallest galaxies hosting SMBHs, and the number of heaviest BHs in the NSC. It is also exponentially sensitive to the radial number density profile exponent, reaching $>100 \, \mathrm{Gpc^{-3}yr^{-1}}$ when the BH mass function is $m^{-2.3}$ or shallower and the heaviest BH radial number density is close to $r^{-3}$. Even if the rate is much lower than the range constrained by the current LIGO detections, the GW captures around SMBHs can be distinguished by their high eccentricity in the LIGO band., 14 pages, 6 figures
- Published
- 2019
12. Bradatica from the Strzelińskie Hills
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Ewa Lisowska
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Archeology ,Sphere of influence (black hole) ,Geography ,Outcrop ,Iron Age ,Human settlement ,Excavation ,Middle Ages ,Archaeology ,Foreland basin ,Mesolithic - Abstract
The excavations in the Strzelińskie Hills, regularly conducted for more than 10 years led to discoveries of many interesting sites. In 2015 was examined the area of the Borowe Skałki located on the slopes of the Gromnik - the highest peak of the Strzelińskie Hills. In the vicinity of the rock outcrops were encountered traces of settlements from the Upper Palaeolithic, the Mesolithic, the Iron Age as well as the early and late Middle Ages. Also an iron battleaxe, the so-called bradatica was found associated with the Great Moravian influence. This artefact belongs to relatively rare finds. From the area of south-west Poland it is the seventh battleaxe of this type, and yet one of the best preserved. This find sheds a new light on the other artefacts from the early Middle Ages in the Strzelińskie Hills, which allow to identify new links between this part of the Sudetes Foreland an the Great Moravian sphere of influence.
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- 2017
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13. Items and proposals related to the suburban area-planning within the big city sphere of influence
- Author
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O. Zavalniy, A. Pankeieva, and K. Viatkin
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Geography ,Sphere of influence (black hole) ,Suburban area ,Economic geography - Abstract
The paper is dedicated to the major aspects of formation and functioning of the suburban areas within the big city sphere of influence. A set of questions was determined to be studied, in particular, definition of essence of the concept of “suburban area”, definitions of suburban area. The new trend of territorial development is the processes of population decentering from the central districts per city, which is related to the factors of development of the objects of social and economic support of the population, as well as a number of environmental problems. The paper proposes a model of suburban area territory planning within the big city sphere of influence, which allows managing and using territories of suburban area a more efficient way.
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- 2020
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14. A Precision Measurement of the Mass of the Black Hole in NGC 3258 from High-Resolution ALMA Observations of its Circumnuclear Disk
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Luis C. Ho, David A. Buote, Aaron J. Barth, Jonelle L. Walsh, Jeremy Darling, Andrew Baker, and Benjamin D. Boizelle
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Physics ,Supermassive black hole ,Sphere of influence (black hole) ,010504 meteorology & atmospheric sciences ,Stellar mass ,Extinction (astronomy) ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Submillimeter Array ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,0103 physical sciences ,Elliptical galaxy ,Astrophysics::Earth and Planetary Astrophysics ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,0105 earth and related environmental sciences ,Line (formation) - Abstract
We present $\sim0.10^{\prime\prime}-$resolution Atacama Large Millimeter/submillimeter Array (ALMA) CO(2$-$1) imaging of the arcsecond-scale ($r \approx 150$ pc) dusty molecular disk in the giant elliptical galaxy NGC 3258. The data provide unprecedented resolution of cold gas disk kinematics within the dynamical sphere of influence of a supermassive black hole, revealing a quasi-Keplerian central increase in projected rotation speed rising from 280 km s$^{-1}$ at the disk's outer edge to $>400$ km s$^{-1}$ near the disk center. We construct dynamical models for the rotating disk and fit beam-smeared model CO line profiles directly to the ALMA data cube. Our models incorporate both flat disks and tilted-ring disks that provide a better fit of the mildly warped structure in NGC 3258. We show that the exceptional angular resolution of the ALMA data makes it possible to infer the host galaxy's mass profile within $r=150$ pc solely from the ALMA CO kinematics, without relying on optical or near-infrared imaging data to determine the stellar mass profile. Our model therefore circumvents any uncertainty in the black hole mass that would result from the substantial dust extinction in the galaxy's central region. The best model fit yields $M_\mathrm{BH} = 2.249\times10^9$ $M_\odot$ with a statistical model-fitting uncertainty of just 0.18\%, and systematic uncertainties of 0.62\% from various aspects of the model construction and 12\% from uncertainty in the distance to NGC 3258. This observation demonstrates the full potential of ALMA for carrying out highly precise measurements of $M_\mathrm{BH}$ in early-type galaxies containing circumnuclear gas disks, Accepted for publication in ApJ. 32 pages, 22 figures
- Published
- 2019
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15. Black Holes as Cosmic Dynamos
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Roger Blandford
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Physics ,High Energy Astrophysical Phenomena (astro-ph.HE) ,Jet (fluid) ,Sphere of influence (black hole) ,Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,Radius ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Accretion (astrophysics) ,Particle acceleration ,Astrophysical jet ,Emission spectrum ,Astrophysics - High Energy Astrophysical Phenomena ,Astrophysics::Galaxy Astrophysics ,Dynamo - Abstract
An introduction is given to a meeting on the role of massive and stellar black holes in powering non-thermal activity in a rich variety of cosmic sources. Relevant properties of magnetized, spinning black holes are summarized and their observational expression, within galactic nuclei, in terms of radio loudness and Fanaroff-Riley class, is briefly described. The dependence of the accretion mode on the rate and manner of the mass supply beyond the black hole sphere of influence is also discussed. It is argued that hydromagnetic outflows from accretion disks are generally expected over as many as six decades of radius and that they may be the source of emission line gas. These outflows collimate the relativistic jets which are probably generated in an electromagnetic form but become hydromagnetic as they entrain gas through boundary layers where most of the initial nonthermal emission occurs. It is proposed that the particle acceleration close to the hole emphasizes the proton channel which allows secondary pairs to be created at far higher energies than is possible from direct acceleration. These pairs radiate synchrotron gamma-rays which can escape along the jet because the outflow effectively shields them from pair-producing, soft photons. Jets are subject to helical instabilities which can tangle their magnetic field and may destroy them. The jet should become plasma-dominated through intermittent, "magnetoluminescent" untangling of the field which causes nonthermal emission all along its length. Powerful jets remain supersonic out to the "hot spots" at the extremities of the source; weaker jets become subsonic plumes or bubbles. The prospects for learning much more about the nature and operation of jets over the next decade are excellent., Comment: 12pp
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- 2019
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16. THE CURRENT STATE OF THE EURASIAN ARC OF INSTABILITY: THE SPHERES OF INFLUENCE AND THE SHIFT OF INSTABILITY FROM THE WESTERN TO THE EASTERN FLANK
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Vladimir Kolotov
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Arc (geometry) ,eurasian arc of instability ,Political science (General) ,Paleontology ,china’s rise ,Sphere of influence (black hole) ,Geography ,Meteorology ,regional controlled destabilization ,General Medicine ,Geopolitics ,“arab spring” ,JA1-92 - Abstract
This article focuses on the general analysis of the present situation along the Eurasian Arc of Instability, as well as comparison of geopolitical processes simultaneously going on its western and eastern flanks. Currently, the Eurasian Arc of Instability for the first time in the history stretches from the Pacific to the Atlantic Ocean and has numerous offshoots, which like the tentacles entangle countries and regions trapped in its sphere of influence, plunging them into the abyss of a long-term controlled destabilization. The fundamental geopolitical contradictions between the global and regional actors in Eurasia provide a permanent upgrade of this “Bickford fuse” and its “burning” in the direction from west to east.
- Published
- 2015
17. Sphere of Influence—'culture'
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John W. Gardner
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Physics ,Classical mechanics ,Sphere of influence (black hole) - Published
- 2017
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18. The North American sphere of influence
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John M. Heffron
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Physics ,Sphere of influence (black hole) ,Classical mechanics - Published
- 2017
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19. A close-pair binary in a distant triple supermassive black hole system
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Sándor Frey, Ian Heywood, K. J. B. Grainge, Rob Fender, Clare Rumsey, Roger Deane, Gianni Bernardi, Hans-Rainer Klöckner, Mickael Coriat, Matt J. Jarvis, and Zsolt Paragi
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High Energy Astrophysical Phenomena (astro-ph.HE) ,Physics ,Supermassive black hole ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,Multidisciplinary ,Sphere of influence (black hole) ,Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,Astronomy ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Black hole ,General Relativity and Quantum Cosmology ,Binary black hole ,Intermediate-mass black hole ,Astrophysics of Galaxies (astro-ph.GA) ,Stellar black hole ,Spin-flip ,Astrophysics - High Energy Astrophysical Phenomena ,Schwarzschild radius ,Astrophysics::Galaxy Astrophysics ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
Galaxies are believed to evolve through merging, which should lead to multiple supermassive black holes in some. There are four known triple black hole systems, with the closest pair being 2.4 kiloparsecs apart (the third component is more distant at 3 kiloparsecs), which is far from the gravitational sphere of influence of a black hole with mass $\sim$10$^9$ M$_\odot$ (about 100 parsecs). Previous searches for compact black hole systems concluded that they were rare, with the tightest binary system having a separation of 7 parsecs. Here we report observations of a triple black hole system at redshift z=0.39, with the closest pair separated by $\sim$140 parsecs. The presence of the tight pair is imprinted onto the properties of the large-scale radio jets, as a rotationally-symmetric helical modulation, which provides a useful way to search for other tight pairs without needing extremely high resolution observations. As we found this tight pair after searching only six galaxies, we conclude that tight pairs are more common than hitherto believed, which is an important observational constraint for low-frequency gravitational wave experiments., 21 pages, 6 figures. Published online by Nature on 25 June 2014. Extremely minor differences with published version exist
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- 2014
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20. Tidal Disruption Events, Main-sequence Extreme-mass Ratio Inspirals, and Binary Star Disruptions in Galactic Nuclei
- Author
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Re'em Sari and Giacomo Fragione
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Sphere of influence (black hole) ,010504 meteorology & atmospheric sciences ,Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,01 natural sciences ,0103 physical sciences ,Binary star ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,0105 earth and related environmental sciences ,High Energy Astrophysical Phenomena (astro-ph.HE) ,Physics ,Supermassive black hole ,Galactic Center ,Stellar collision ,Astronomy and Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Stars ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics - High Energy Astrophysical Phenomena ,Schwarzschild radius - Abstract
The Galactic Center has been under intense scrutiny in the recent years thanks to the unprecedented missions aiming at measuring the gas and star dynamics near the supermassive black hole (SMBH) and at finding gravitational wave (GW) signatures of inspiralling stellar black holes. In the crowded environment of galactic nuclei, the two-body interactions alter the distribution of stars on long timescales, making them drift in energy and angular momentum. We present a simplified analytical treatment of the scattering processes in galactic stellar nuclei, assuming all stars have the same mass. We have discussed how the interplay between two-body relaxation and gravitational wave emission modifies the slope of the inner stellar cusp within the SMBH sphere of influence, and calculated the rates of tidal disruption events (TDEs) and main-sequence extreme-mass ratio inspirals (MS-EMRIs) of stars that are tidally disrupted by the SMBH. We find that typically the ratio of the TDE and MS-EMRI rates is the square of the ratio of the tidal and Schwarzschild radii. For our Galaxy, this implies that the rate of MS-EMRIs is just about a percent of the TDE rate. We then consider the role of stars injected on highly eccentric orbits in the vicinity of the SMBH due to Hills binary disruption mechanism, and show that the MS-EMRI rate can almost approach the TDE rate if the binary fraction at the SMBH influence radius is close to unity. Finally, we discuss that physical stellar collisions affect a large area of phase space., 9 pages, 4 figures, accepted by ApJ
- Published
- 2019
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21. The strategic interests of the USA, Russia and Сhina in the central Asia at the present stage
- Author
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Tofan A.V.
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lcsh:Social Sciences ,lcsh:H ,China ,Sphere of influence (black hole) ,geostrategy ,Political science ,the USA ,geopolitics ,lcsh:Q ,The Central Asia ,lcsh:Science ,Humanities ,Russia - Abstract
this article is devoted to develop and analyze the strategic concerns of key geopolitical actors in the Central Asian region. The author comes to the conclusion that the specialty of the Central Asia is a beneficial geopolitical location and great amount of nature resources that makes the region an object of world powers’ geopolitical interests. The main actors in the CA are the USA, China and Russia, which have influence on political processes inside the region, realizing their own strategies.
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- 2016
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22. The central black hole mass of the high-σ but low-bulge-luminosity lenticular galaxy NGC 1332★
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S. P. Rusli, Roberto P. Saglia, Jens Thomas, Nina Nowak, Ralf Bender, and Peter Erwin
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Physics ,Supermassive black hole ,Sphere of influence (black hole) ,Astrophysics::High Energy Astrophysical Phenomena ,Sigma ,Velocity dispersion ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Galaxy ,Luminosity ,Black hole ,Space and Planetary Science ,Bulge ,Astrophysics::Galaxy Astrophysics - Abstract
The masses of the most massive supermassive black holes (SMBHs) predicted by the M_BH-sigma and M_BH-luminosity relations appear to be in conflict. Which of the two relations is the more fundamental one remains an open question. NGC 1332 is an excellent example that represents the regime of conflict. It is a massive lenticular galaxy which has a bulge with a high velocity dispersion sigma of ~320 km/s; bulge--disc decomposition suggests that only 44% of the total light comes from the bulge. The M_BH-sigma and the M_BH-luminosity predictions for the central black hole mass of NGC 1332 differ by almost an order of magnitude. We present a stellar dynamical measurement of the SMBH mass using an axisymmetric orbit superposition method. Our SINFONI integral-field unit (IFU) observations of NGC 1332 resolve the SMBH's sphere of influence which has a diameter of ~0.76 arcsec. The sigma inside 0.2 arcsec reaches ~400 km/s. The IFU data allow us to increase the statistical significance of our results by modelling each of the four quadrants separately. We measure a SMBH mass of (1.45 \pm 0.20) x 10^9 M_sun with a bulge mass-to-light ratio of 7.08 \pm 0.39 in the R-band. With this mass, the SMBH of NGC 1332 is offset from the M_BH-luminosity relation by a full order of magnitude but is consistent with the M_BH-sigma relation.
- Published
- 2010
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23. Swimming against the current: simulations of central AGN evolution in dynamic galaxy clusters
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Marcus Brüggen, Sebastian Heinz, Mateusz Ruszkowski, and Brian J. Morsony
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Physics ,Jet (fluid) ,Sphere of influence (black hole) ,010308 nuclear & particles physics ,Astrophysics::High Energy Astrophysical Phenomena ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Radius ,01 natural sciences ,Luminosity ,Core (optical fiber) ,Space and Planetary Science ,0103 physical sciences ,Magnitude (astronomy) ,Cluster (physics) ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Galaxy cluster - Abstract
We present a series of three-dimensional hydrodynamical simulations of central AGN driven jets in a dynamic, cosmologically evolved galaxy cluster. Extending previous work, we study jet powers ranging from L_jet = 10^44 erg/s to L_jet = 10^46 erg/s and in duration from 30 Myr to 200 Myr. We find that large-scale motions of cluster gas disrupt the AGN jets, causing energy to be distributed throughout the centre of the cluster, rather than confined to a narrow angle around the jet axis. Disruption of the jet also leads to the appearance of multiple disconnected X-ray bubbles from a long-duration AGN with a constant luminosity. This implies that observations of multiple bubbles in a cluster are not necessarily an expression of the AGN duty cycle. We find that the "sphere of influence" of the AGN, the radial scale within which the cluster is strongly affected by the jet, scales as R ~ L_jet^(1/3). Increasing the duration of AGN activity does not increase the radius affected by the AGN significantly, but does change the magnitude of the AGN's effects. How an AGN delivers energy to a cluster will determine where that energy is deposited: a high luminosity is needed to heat material outside the core of the cluster, while a low-luminosity, long-duration AGN is more efficient at heating the inner few tens of kpc.
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- 2010
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24. A Fundamental Test for Galaxy Formation Models: Matching the Lyman-αAbsorption Profiles of Galactic Halos Over Three Decades in Distance
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Zarija Lukić, Joseph F. Hennawi, Jose Oñorbe, and Daniele Sorini
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Physics ,Sphere of influence (black hole) ,010308 nuclear & particles physics ,Astronomy and Astrophysics ,Quasar ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Radius ,Astrophysics - Astrophysics of Galaxies ,01 natural sciences ,Virial theorem ,Galaxy ,Supernova ,Space and Planetary Science ,0103 physical sciences ,Galaxy formation and evolution ,Halo ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
Galaxy formation depends critically on the physical state of gas in the circumgalactic medium (CGM) and its interface with the intergalactic medium (IGM), determined by the complex interplay between inflows from the IGM and outflows from supernovae or AGN feedback. The average Lyman-alpha (Ly-a) absorption profile around galactic halos represents a powerful tool to probe their gaseous environments. We compare predictions from Illustris and Nyx hydrodynamical simulations with the observed absorption around foreground quasars, damped Ly-a systems, and Lyman-break galaxies. We show how large-scale BOSS and small-scale quasar pair measurements can be combined to precisely constrain the absorption profile over three decades in transverse distance 20kpc$\lesssim b\lesssim$20Mpc. Far from galaxies $\gtrsim2$Mpc, the simulations converge to the same profile and provide a reasonable match to the observations. This asymptotic agreement arises because the $\Lambda$CDM model successfully describes the ambient IGM, and represents a critical advantage of studying the mean absorption profile. However, significant differences between the simulations, and between simulations and observations are present on scales 20kpc$\lesssim b\lesssim$2Mpc, illustrating the challenges of accurately modeling and resolving galaxy formation physics. It is noteworthy that these differences are observed as far out as $\sim2$Mpc, indicating that the `sphere-of-influence' of galaxies could extend to approximately $\sim7$ times the halo virial radius ($\sim100$kpc). Current observations are very precise on these scales and can thus strongly discriminate between different galaxy formation models. We demonstrate that the Ly-a absorption profile is primarily sensitive to the underlying temperature-density relationship of diffuse gas around galaxies, and argue that it thus provides a fundamental test of galaxy formation models., Comment: Published in ApJ. This is the Accepted Manuscript version of an article accepted for publication in The Astrophysical Journal. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. The Version of Record is available online at https://iopscience.iop.org/article/10.3847/1538-4357/aabb52
- Published
- 2018
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25. Determination of masses of the central black holes in NGC 524 and 2549 using laser guide star adaptive optics
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Davor Krajnović, Michele Cappellari, Roger L. Davies, and Richard M. McDermid
- Subjects
Physics ,Supermassive black hole ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,Sphere of influence (black hole) ,010308 nuclear & particles physics ,FOS: Physical sciences ,Sigma ,Astronomy and Astrophysics ,Astrophysics ,Astrophysics - Astrophysics of Galaxies ,01 natural sciences ,Galaxy ,law.invention ,Telescope ,Laser guide star ,Space and Planetary Science ,law ,Astrophysics of Galaxies (astro-ph.GA) ,0103 physical sciences ,Anisotropy ,Adaptive optics ,010303 astronomy & astrophysics ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
[abridged] We present observations of NGC524 and NGC2549 with LGS AO obtained at GEMINI North telescope using the NIFS IFU in the K band. The purpose of these observations, together with previously obtained observations with the SAURON IFU, is to determine the masses (Mbh) of the supermassive black holes (SMBH). The targeted galaxies were chosen to have central light profiles showing a core (NGC524) and a cusp (NGC2549), to probe the feasibility of using the galaxy centre as the NGS required for LGS AO. We employ an innovative `open loop' technique. The data have spatial resolution of 0.23" and 0.17" FWHM, showing that high quality LGS AO observations of these objects are possible. We construct axisymmetric three-integral dynamical models which are constrained with both the NIFS and SAURON data. The best fitting models yield Mbh=(8.3 +2.7 -1.3) x 10^8 Msun for NGC524 and Mbh=(1.4 +0.2 -1.3) x 10^7 Msun for NGC2549 (all errors are at the 3 sigma CL). We demonstrate that the wide-field SAURON data play a crucial role in the M/L determination increasing the accuracy of M/L by a factor of at least 5, and constraining the upper limits on Mbh. The NIFS data are crucial in constraining the lower limits of Mbh and in combination with the large scale data reducing the uncertainty by a factor of 2 or more. We find that the orbital structure of NGC524 shows significant tangential anisotropy, while at larger radii both galaxies are consistent with having almost perfectly oblate velocity ellipsoids. Tangential anisotropy in NGC524 coincides with the size of SMBH sphere of influence and the core region in the light profile. We test the accuracy to which Mbh can be measured using seeings obtained from typical LGS AO observations, and conclude that for a typical conditions and Mbh the expected uncertainty is of the order of 50%., 19 pages, 14 figures
- Published
- 2009
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26. Determination of the Intrinsic Scatter in the MBH–σ and MBH–Lbulge Relations
- Author
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Kayhan Gültekin
- Subjects
Physics ,Black hole ,Supermassive black hole ,Sphere of influence (black hole) ,Space and Planetary Science ,Bulge ,Velocity dispersion ,Astronomy and Astrophysics ,Spin-flip ,Astrophysics ,Lenticular galaxy ,Luminosity - Abstract
We derive improved versions of the relations between supermassive black hole mass MBH and host-galaxy bulge velocity dispersion σ and luminosity L (the MBH–σ and MBH–Lbulge relations), based on ~ 50 MBH measurements and ~ 20 upper limits. Particular attention is paid to recovery of the intrinsic scatter (ϵ0) in both relations. We find the scatter to be significantly larger than estimated in most previous studies. The large scatter requires revision of the local black hole mass function, and it implies that there may be substantial selection bias in studies of the evolution of the MBH–σ and MBH–Lbulge relations. When only considering ellipticals, the scatter decreases. These results appear to be insensitive to a wide range of assumptions about the measurement errors and the distribution of intrinsic scatter. We also investigate the effects on the fits of culling the sample according to the resolution of the black hole's sphere of influence.
- Published
- 2009
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27. Influencing through Social Media: Expanding Your Sphere of Influence
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B. Kim Barnes
- Subjects
Sphere of influence (black hole) ,Media studies ,Social media ,Sociology ,Social psychology - Published
- 2015
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28. Micrometeoroid impact crater statistics at the boundary of Earth's gravitational sphere of influence
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Stanley G. Love and Judith H. Allton
- Subjects
Physics ,education.field_of_study ,Earth's orbit ,Solar System ,Sphere of influence (black hole) ,Micrometeoroid ,Population ,Astronomy ,Astronomy and Astrophysics ,Physics::Geophysics ,Interplanetary dust cloud ,Impact crater ,Space and Planetary Science ,Physics::Space Physics ,Satellite ,Astrophysics::Earth and Planetary Astrophysics ,education - Abstract
We surveyed craters on a space-exposed surface from the Genesis solar wind sample return mission to find new constraints on the population of micrometeoroids at the edge of the Earth's gravitational sphere of influence. The target was made of 6061-T6 aluminum, identical to the composition of the space-facing end of the Long Duration Exposure Facility satellite, which recorded micrometeoroid impacts in low Earth orbit. We use data from both locations to compare crater frequency as a function of size, with and without gravitational focussing by the Earth. We find that the cratering flux near the Earth–Sun L1 libration point is indistinguishable, within the ∼ 40 % uncertainty of this study, from that in low Earth orbit. The small degree of gravitational focussing between the two locations indicates that particles with geocentric free-space velocities less than a few kilometers per second comprise no more than a few percent of the interplanetary dust complex.
- Published
- 2006
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29. Leading beyond your formal sphere of influence
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Major Everett S. P. Spain
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Physics ,Classical mechanics ,Sphere of influence (black hole) - Published
- 2005
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30. Analysis and Simulation of Group Behavior Using a Dynamic Sphere of Influence
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Tsuyoshi Taki and Junichi Hasegawa
- Subjects
Human-Computer Interaction ,Classical mechanics ,Sphere of influence (black hole) ,Artificial Intelligence ,Computer science ,Group behavior ,Computer Vision and Pattern Recognition ,Simulation - Abstract
To evaluate or predict human behavior, extraction of characteristic patterns from actual crowd scenes and crowd simulation in different situations based on general human behavior model are needed. We use changes in a spatial feature formed by individual movement called a "dominant region", a type of dynamic personal space. In the paper, a basic concept and calculation of the dominant region and its applications are presented. Experiments show that the proposed feature is useful in evaluating and simulating human behavior.
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- 2005
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31. Difficulties with Recovering the Masses of Supermassive Black Holes from Stellar Kinematical Data
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David Merritt, Monica Valluri, and Eric Emsellem
- Subjects
Physics ,Supermassive black hole ,Solar mass ,Sphere of influence (black hole) ,010308 nuclear & particles physics ,Astrophysics (astro-ph) ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,01 natural sciences ,Galaxy ,Black hole ,Gravitational potential ,Space and Planetary Science ,0103 physical sciences ,Degeneracy (mathematics) ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Smoothing - Abstract
We investigate the ability of three-integral, axisymmetric, orbit-based modeling algorithms to recover the parameters defining the gravitational potential (M/L ratio and black hole mass Mh) in spheroidal stellar systems using stellar kinematical data. We show that the potential estimation problem is generically under-determined when applied to long-slit kinematical data of the kind used in most black hole mass determinations to date. A range of parameters (M/L, Mh) can provide equally good fits to the data, making it impossible to assign best-fit values. We illustrate the indeterminacy using a variety of data sets derived from realistic models as well as published observations of the galaxy M32. In the case of M32, our reanalysis demonstrates that data published prior to 2000 are equally consistent with Mh in the range 1.5x10^6-5x10^6 solar masses, with no preferred value in that range. While the HST/STIS data for this galaxy may overcome the degeneracy in Mh, HST data for most galaxies do not resolve the black hole's sphere of influence and in these galaxies the degree of degeneracy allowed by the data may be substantial. We investigate the effect on the degeneracy of enforcing smoothness (regularization) constraints. However we find no indication that the true potential can be recovered simply by enforcing smoothness. For a given smoothing level, all solutions in the minimum-chisquare valley exhibit similar levels of noise. These experiments affirm that the indeterminacy is real and not an artifact associated with non-smooth solutions. (Abridged), Comment: Accepted for publication in The Astrophysical Journal. Changes include discussion of regularization
- Published
- 2004
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32. THE IMPACT OF SOCIAL MEDIA ON CARDIOVASCULAR MEDICINE: INSIGHTS INTO TWITTER'S SPHERE OF INFLUENCE
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Pishoy Gouda, Alexander M. Clark, Justin A. Ezekowitz, and Debraj Das
- Subjects
Sphere of influence (black hole) ,business.industry ,Media studies ,Medicine ,Social media ,Cardiology and Cardiovascular Medicine ,business - Published
- 2016
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33. The Black Hole in the Compact, High-dispersion Galaxy NGC 1271
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Douglas O. Richstone, Jonelle L. Walsh, Akın Yıldırım, Karl Gebhardt, Remco C. E. van den Bosch, Kayhan Gültekin, and Bernd Husemann
- Subjects
Physics ,Stellar kinematics ,Sphere of influence (black hole) ,Astrophysics::High Energy Astrophysical Phenomena ,Velocity dispersion ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Luminosity ,Black hole ,General Relativity and Quantum Cosmology ,Space and Planetary Science ,Bulge ,Astrophysics of Galaxies (astro-ph.GA) ,Elliptical galaxy ,Astrophysics::Solar and Stellar Astrophysics ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics::Galaxy Astrophysics - Abstract
Located in the Perseus cluster, NGC 1271 is an early-type galaxy with a small effective radius of 2.2 kpc and a large stellar velocity dispersion of 276 km/s for its K-band luminosity of 8.9x10^{10} L_sun. We present a mass measurement for the black hole in this compact, high-dispersion galaxy using observations from the integral field spectrograph NIFS on the Gemini North telescope assisted by laser guide star adaptive optics, large-scale integral field unit observations with PPAK at the Calar Alto Observatory, and Hubble Space Telescope WFC3 imaging observations. We are able to map out the stellar kinematics on small spatial scales, within the black hole sphere of influence, and on large scales that extend out to four times the galaxy's effective radius. We find that the galaxy is rapidly rotating and exhibits a sharp rise in the velocity dispersion. Through the use of orbit-based stellar dynamical models, we determine that the black hole has a mass of (3.0^{+1.0}_{-1.1}) x 10^9 M_sun and the H-band stellar mass-to-light ratio is 1.40^{+0.13}_{-0.11} M_sun/L_sun (1-sigma uncertainties). NGC 1271 occupies the sparsely-populated upper end of the black hole mass distribution, but is very different from the Brightest Cluster Galaxies (BCGs) and giant elliptical galaxies that are expected to host the most massive black holes. Interestingly, the black hole mass is an order of magnitude larger than expectations based on the galaxy's bulge luminosity, but is consistent with the mass predicted using the galaxy's bulge stellar velocity dispersion. More compact, high-dispersion galaxies need to be studied using high spatial resolution observations to securely determine black hole masses, as there could be systematic differences in the black hole scaling relations between these types of galaxies and the BCGs/giant ellipticals, thereby implying different pathways for black hole and galaxy growth., Comment: accepted for publication in ApJ
- Published
- 2015
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34. Effective power-law dependence of Lyapunov exponents on the central mass in galaxies
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Christos Efthymiopoulos, Constantinos Kalapotharakos, and N. Delis
- Subjects
Physics ,Supermassive black hole ,Sphere of influence (black hole) ,Galaxies: kinematics and dynamics ,FOS: Physical sciences ,Astronomy and Astrophysics ,Lyapunov exponent ,Disc galaxy ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,symbols.namesake ,Galaxies: structure ,Space and Planetary Science ,Quantum mechanics ,Chaotic scattering ,Law ,Astrophysics of Galaxies (astro-ph.GA) ,symbols ,Elliptical galaxy ,Chaos ,Lindblad resonance - Abstract
Using both numerical and analytical approaches, we demonstrate the existence of an effective power-law relation $L\propto m^p$ between the mean Lyapunov exponent $L$ of stellar orbits chaotically scattered by a supermassive black hole in the center of a galaxy and the mass parameter $m$, i.e. ratio of the mass of the black hole over the mass of the galaxy. The exponent $p$ is found numerically to obtain values in the range $p \approx 0.3$--$0.5$. We propose a theoretical interpretation of these exponents, based on estimates of local `stretching numbers', i.e. local Lyapunov exponents at successive transits of the orbits through the black hole's sphere of influence. We thus predict $p=2/3-q$ with $q\approx 0.1$--$0.2$. Our basic model refers to elliptical galaxy models with a central core. However, we find numerically that an effective power law scaling of $L$ with $m$ holds also in models with central cusp, beyond a mass scale up to which chaos is dominated by the influence of the cusp itself. We finally show numerically that an analogous law exists also in disc galaxies with rotating bars. In the latter case, chaotic scattering by the black hole affects mainly populations of thick tube-like orbits surrounding some low-order branches of the $x_1$ family of periodic orbits, as well as its bifurcations at low-order resonances, mainly the Inner Lindbland resonance and the 4/1 resonance. Implications of the correlations between $L$ and $m$ to determining the rate of secular evolution of galaxies are discussed., Comment: 27 pages, 19 figures
- Published
- 2015
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35. Editorial: Invisible Sphere of Influence
- Author
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Jacqueline Snider
- Subjects
Physics ,Sphere of influence (black hole) ,Classical mechanics - Abstract
Among the many fine articles in this issue, the topic of mentorship strikes a chord. Jeremy Denk in a recent New Yorker recalls several of his piano teachers. During one of his recitals, he played some unintended notes. He heard his former teacher’s voice in his head, telling him not to be a perfectionist. How many of us conjure up the ghosts of former mentors or teachers while we are struggling, trying to make sense? [...]
- Published
- 2017
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36. The Mass of the Central Black Hole in the Nearby Seyfert Galaxy NGC5273
- Author
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K. G. Teems, C. Bazhaw, Matthew D. Anderson, Jeremy Jones, C. S. Turner, Ryan Norris, D. Horenstein, D. A. Saylor, Misty C. Bentz, E. R. Manne-Nicholas, J. Robert Parks, and B. Ou-Yang
- Subjects
Physics ,Time delays ,Active galactic nucleus ,Dynamical modeling ,Sphere of influence (black hole) ,010308 nuclear & particles physics ,Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Continuum flux ,01 natural sciences ,Monitoring program ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Black hole ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,0103 physical sciences ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics - Abstract
We present the results of a reverberation-mapping program targeting NGC5273, a nearby early-type galaxy with a broad-lined active galactic nucleus. Over the course of the monitoring program, NGC5273 showed strong variability that allowed us to measure time delays in the responses of the broad optical recombination lines to changes in the continuum flux. A weighted average of these measurements results in a black hole mass determination of $M_{\rm BH} = (4.7 \pm 1.6) \times 10^6$ M$_{\odot}$. An estimate of the size of the black hole sphere of influence in NGC5273 puts it just at the limit of the resolution achievable with current ground-based large aperture telescopes. NGC5273 is therefore an important future target for a black hole mass determination from stellar dynamical modeling, especially because it is the only nearby early-type galaxy hosting an AGN with a reverberation-based mass, allowing the best comparison for the masses determined from these two techniques., 10 pages, 7 figures, 3 tables, accepted for publication in ApJ
- Published
- 2014
37. A figure of merit for black hole mass measurements with molecular gas
- Author
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Timothy A. Davis
- Subjects
Physics ,Supermassive black hole ,Sphere of influence (black hole) ,Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,Astronomy ,Astronomy and Astrophysics ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Black hole ,General Relativity and Quantum Cosmology ,Binary black hole ,Space and Planetary Science ,Intermediate-mass black hole ,Astrophysics of Galaxies (astro-ph.GA) ,Stellar black hole ,Spin-flip ,Schwarzschild radius ,Astrophysics::Galaxy Astrophysics ,QB - Abstract
In this work we discuss the technique of using molecular gas kinematics (or the kinematics of any dynamically cold tracer) to estimate black hole masses. We present a figure of merit that will be useful in defining future observational campaigns, and discuss its implications. We show that, in principle, one can estimate black-hole masses using data that only resolve scales ~2 times the formal black hole sphere of influence, and confirm this by reanalysing lower resolution observations of the molecular gas around the black hole in NGC4526. We go on to discuss the effect that angular resolution, velocity resolution and the depth of the galaxies potential have on the ability to estimate black hole masses, and conclude by discussing prospects for the future. Once ALMA is fully operational, we find that over 10^5 local galaxies with massive black holes will be observable, and that given sufficient surface brightness sensitivity one could measure the mass of a >4x10^8 Msun black hole at any redshift., 9 pages, 7 figures, accepted for publication in MNRAS
- Published
- 2014
38. Turbovelocity Stars: Kicks Resulting From the Tidal Disruption of Solitary Stars
- Author
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Ryan M. O'Leary, James Guillochon, Enrico Ramirez-Ruiz, and Haik Manukian
- Subjects
Physics ,High Energy Astrophysical Phenomena (astro-ph.HE) ,Supermassive black hole ,Sphere of influence (black hole) ,Stellar mass ,Milky Way ,Astrophysics::High Energy Astrophysical Phenomena ,Galactic Center ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Galaxy ,Black hole ,Stars ,Space and Planetary Science ,Astrophysics::Solar and Stellar Astrophysics ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics - High Energy Astrophysical Phenomena ,Astrophysics::Galaxy Astrophysics - Abstract
The centers of most known galaxies host supermassive black holes (SMBHs). In orbit around these black holes are a centrally-concentrated distribution of stars, both in single and in binary systems. Occasionally, these stars are perturbed onto orbits that bring them close to the SMBH. If the star is in a binary system, the three-body interaction with the SMBH can lead to large changes in orbital energy, depositing one of the two stars on a tightly-bound orbit, and its companion into a hyperbolic orbit that may escape the galaxy. In this Letter, we show that the disruption of solitary stars can also lead to large positive increases in orbital energy. The kick velocity depends on the amount of mass the star loses at pericenter, but not on the ratio of black hole to stellar mass, and are at most the star's own escape velocity. We find that these kicks are usually too small to result in the ejection of stars from the Milky Way, but can eject the stars from the black hole's sphere of influence, reducing their probability of being disrupted again. We estimate that ~10^5 stars, ~1% of all stars within 10 pc of the galactic center, are likely to have had mass removed by the central black hole through tidal interaction, and speculate that these "turbovelocity" stars will at first be redder, but eventually bluer, and always brighter than their unharrassed peers., Comment: 6 pages, 5 figures. Published in ApJL, includes erratum which corrects algebra errors in Section 3.2
- Published
- 2013
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39. TOWARD PRECISION BLACK HOLE MASSES WITH ALMA: NGC 1332 AS A CASE STUDY IN MOLECULAR DISK DYNAMICS
- Author
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Benjamin D. Boizelle, David A. Buote, Luis C. Ho, Jeremy Darling, Aaron J. Barth, Jonelle L. Walsh, and Andrew J. Baker
- Subjects
Sphere of influence (black hole) ,bulges [galaxies] ,astro-ph.GA ,Astrophysics::High Energy Astrophysical Phenomena ,Milky Way ,nuclei [galaxies] ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Astronomy & Astrophysics ,Atomic ,01 natural sciences ,Particle and Plasma Physics ,Bulge ,kinematics and dynamics [galaxies] ,0103 physical sciences ,Nuclear ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Physics ,Supermassive black hole ,010308 nuclear & particles physics ,individual (NGC 1332) [galaxies] ,individual [galaxies] ,Molecular ,Astronomy and Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Black hole ,Dark matter halo ,Thin disk ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,Astrophysics::Earth and Planetary Astrophysics ,Astronomical and Space Sciences ,Physical Chemistry (incl. Structural) - Abstract
We present first results from a program of Atacama Large Millimeter/submillimeter Array (ALMA) CO(2-1) observations of circumnuclear gas disks in early-type galaxies. The program was designed with the goal of detecting gas within the gravitational sphere of influence of the central black holes. In NGC 1332, the 0.3"-resolution ALMA data reveal CO emission from the highly inclined (i~ 83 degrees) circumnuclear disk, spatially coincident with the dust disk seen in Hubble Space Telescope images. The disk exhibits a central upturn in maximum line-of-sight velocity reaching +-500 km/s relative to the systemic velocity, consistent with the expected signature of rapid rotation around a supermassive black hole. Rotational broadening and beam smearing produce complex and asymmetric line profiles near the disk center. We constructed dynamical models for the rotating disk and fitted the modeled CO line profiles directly to the ALMA data cube. Degeneracy between rotation and turbulent velocity dispersion in the inner disk precludes the derivation of strong constraints on the black hole mass, but model fits allowing for a plausible range in the magnitude of the turbulent dispersion imply a central mass in the range ~(4-8)x10^8 Msun. We argue that gas-kinematic observations resolving the black hole's projected radius of influence along the disk's minor axis will have the capability to yield black hole mass measurements that are largely insensitive to systematic uncertainties in turbulence or in the stellar mass profile. For highly inclined disks, this is a much more stringent requirement than the usual sphere-of-influence criterion., Comment: 22 pages, 16 figures, accepted for publication in ApJ
- Published
- 2016
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40. Spectroastrometry of rotating gas disks for the detection of supermassive black holes in galactic nuclei. II. Application to the galaxy Centaurus A (NGC 5128)
- Author
-
Andrew Robinson, David J. Axon, A. Gnerucci, Alessandro Marconi, Nadine Neumayer, and Alessandro Capetti
- Subjects
Physics ,Supermassive black hole ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,Sphere of influence (black hole) ,Active galactic nucleus ,Astrophysics::High Energy Astrophysical Phenomena ,Centaurus A ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Radius ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Galaxy ,Black hole ,Space and Planetary Science ,Galaxy rotation curve ,Astrophysics::Galaxy Astrophysics ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We measure the black hole mass in the nearby active galaxy Centaurus A (NGC 5128) using a new method based on spectroastrometry of a rotating gas disk. The spectroastrometric approach consists in measuring the photocenter position of emission lines for different velocity channels. In a previous paper we focused on the basic methodology and the advantages of the spectroastrometric approach with a detailed set of simulations demonstrating the possibilities for black hole mass measurements going below the conventional spatial resolution. In this paper we apply the spectroastrometric method to multiple longslit and integral field near infrared spectroscopic observations of Centaurus A. We find that the application of the spectroastrometric method provides results perfectly consistent with the more complex classical method based on rotation curves: the measured BH mass is nearly independent of the observational setup and spatial resolution and the spectroastrometric method allows the gas dynamics to be probed down to spatial scales of ~0.02", i.e. 1/10 of the spatial resolution and ~1/50 of BH sphere of influence radius. The best estimate for the BH mass based on kinematics of the ionized gas is then log(MBH (sin i)^2/M\odot)=7.5 \pm 0.1 which corresponds to MBH = 9.6(+2.5-1.8) \times 10^7 M\odot for an assumed disk inclination of i = 35deg. The complementarity of this method with the classic rotation curve method will allow us to put constraints on the disk inclination which cannot be otherwise derived from spectroastrometry. With the application to Centaurus A, we have shown that spectroastrometry opens up the possibility of probing spatial scales smaller than the spatial resolution, extending the measured MBH range to new domains which are currently not accessible: smaller BHs in the local universe and similar BHs in more distant galaxies.
- Published
- 2011
41. Observational selection effects and the M-sigma relation
- Author
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Scott Tremaine, Kayhan Gültekin, Abraham Loeb, and Douglas O. Richstone
- Subjects
Physics ,Normalization (statistics) ,Sphere of influence (black hole) ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,Velocity dispersion ,FOS: Physical sciences ,Astronomy and Astrophysics ,Extragalactic astronomy ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics - Astrophysics of Galaxies ,01 natural sciences ,Redshift ,Galaxy ,Confidence interval ,Black hole ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,0103 physical sciences ,010306 general physics ,010303 astronomy & astrophysics ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We examine the possibility that the observed relation between black-hole mass and host-galaxy stellar velocity dispersion (the M-sigma relation) is biased by an observational selection effect, the difficulty of detecting a black hole whose sphere of influence is smaller than the telescope resolution. In particular, we critically investigate recent claims that the M-sigma relation only represents the upper limit to a broad distribution of black-hole masses in galaxies of a given velocity dispersion. We find that this hypothesis can be rejected at a high confidence level, at least for the early-type galaxies with relatively high velocity dispersions (median 268 km/s) that comprise most of our sample. We also describe a general procedure for incorporating observational selection effects in estimates of the properties of the M-sigma relation. Applying this procedure we find results that are consistent with earlier estimates that did not account for selection effects, although with larger error bars. In particular, (i) the width of the M-sigma relation is not significantly increased; (ii) the slope and normalization of the M-sigma relation are not significantly changed; (iii) most or all luminous early-type galaxies contain central black holes at zero redshift. Our results may not apply to late-type or small galaxies, which are not well-represented in our sample., Comment: 8 pages, ApJ accepted
- Published
- 2011
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42. The value of big dreams: our sphere of influence is limited only by our imagination
- Author
-
Sreenivas Koka
- Subjects
Imagination ,Sphere of influence (black hole) ,media_common.quotation_subject ,Dentistry (miscellaneous) ,Oral Surgery ,Value (mathematics) ,Prosthodontics ,Mathematics ,Epistemology ,media_common - Published
- 2010
43. Effect of a dark matter halo on the determination of black hole masses
- Author
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Karl Gebhardt and Andreas Schulze
- Subjects
Physics ,Stellar kinematics ,Dynamical modeling ,Sphere of influence (black hole) ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,010308 nuclear & particles physics ,Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Galaxy ,Black hole ,Dark matter halo ,Orbit ,General Relativity and Quantum Cosmology ,Space and Planetary Science ,Hubble space telescope ,0103 physical sciences ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
Stellar dynamical modeling is a powerful method to determine the mass of black holes in quiescent galaxies. However, in previous work the presence of a dark matter halo has been ignored in the modeling. Gebhardt & Thomas (2009) showed that accounting for a dark matter halo increased the black hole mass of the massive galaxy M87 by a factor of two. We used a sample of 12 galaxies to investigate the effect of accounting for a dark matter halo in the dynamical modeling in more detail, and also updated the masses using improved modeling. The sample of galaxies possesses Hubble Space Telescope and ground based observations of stellar kinematics. Their black hole masses have been presented before, but without including a dark matter halo in the models. Without a dark halo, we find a mean increase in the estimated mass of 1.5 for the whole sample compared to previous results. We attribute this change to using a more complete orbit library. When we include a dark matter halo, along with the updated models, we find an additional increase in black hole mass by a factor of 1.2 in the mean, much less than for M87. We attribute the smaller discrepancy in black hole mass to using data that better resolves the black hole's sphere of influence. We redetermined the M-sigma and M-L relationships using our updated black hole masses and found a slight increase in both normalization and intrinsic scatter., 14 pages, 10 figures, accepted for publication in ApJ
- Published
- 2010
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44. The M-Sigma Relation Derived from Sphere of Influence Arguments
- Author
-
Dan Batcheldor
- Subjects
Physics ,education.field_of_study ,Supermassive black hole ,Sphere of influence (black hole) ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,Relation (database) ,Population ,Velocity dispersion ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Space and Planetary Science ,Bulge ,Astrophysics of Galaxies (astro-ph.GA) ,Limit (mathematics) ,education ,Astrophysics::Galaxy Astrophysics ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
The observed relation between supermassive black hole (SMBH) mass (M) and bulge stellar velocity dispersion (Sigma) is described by log(M) = alpha + beta*log(Sigma/200 km/s). As this relation has important implications for models of galaxy and SMBH formation and evolution, there continues to be great interest in adding to the M catalog. The "sphere of influence" (r) argument uses spatial resolution to exclude some M estimates and pre-select additional galaxies for further SMBH studies. This Letter quantifies the effects of applying the r argument to a population of galaxies and SMBHs that do not follow the M-Sigma relation. All galaxies with known values of Sigma, closer than 100 Mpc, are given a random M and selected when r is spatially resolved. These random SMBHs produce an M-Sigma relation of alpha=8.3, beta=4.0, consistent with observed values. Consequently, future proposed M estimates should not be justified solely on the basis of resolving r. This Letter shows the observed M-Sigma relation may simply be a result of available spatial resolution. However, it also implies the observed M-Sigma relation defines an upper limit. This potentially provides valuable new insight into the processes of galaxy and SMBH formation and evolution., Comment: ApJ Letters, accepted
- Published
- 2010
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45. A Quintet of Black Hole Mass Determinations
- Author
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Tod R. Lauer, Karl Gebhardt, Ralf Bender, Kayhan Gültekin, Richard F. Green, Jason Pinkney, Monique Aller, Christos Siopis, John Kormendy, Alexei V. Filippenko, Luis C. Ho, Douglas O. Richstone, Sandra M. Faber, and Alan Dressler
- Subjects
Physics ,Solar mass ,Sphere of influence (black hole) ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,Astrophysics::High Energy Astrophysical Phenomena ,Velocity dispersion ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Type (model theory) ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Black hole ,Space and Planetary Science ,Hubble space telescope ,Astrophysics of Galaxies (astro-ph.GA) ,Schwarzschild radius ,Astrophysics::Galaxy Astrophysics ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We report five new measurements of central black hole masses based on STIS and WFPC2 observations with the Hubble Space Telescope and on axisymmetric, three-integral, Schwarzschild orbit-library kinematic models. We selected a sample of galaxies within a narrow range in velocity dispersion that cover a range of galaxy parameters (including Hubble type and core/power-law surface density profile) where we expected to be able to resolve the galaxy's sphere of influence based on the predicted value of the black hole mass from the M-sigma relation. We find masses in units of 10^8 solar masses for the following galaxies: NGC 3585, M_BH = 3.4 (+1.5, -0.6); NGC 3607, M_BH = 1.2 (+0.4, -0.4); NGC 4026, M_BH = 2.1 (+0.7, -0.4); and NGC 5576, M_BH = 1.8 (+0.3, -0.4), all significantly excluding M_BH = 0. For NGC 3945, M_BH = 0.09 (+0.17, -0.21), which is significantly below predictions from M-sigma and M-L relations and consistent with M_BH = 0, though the presence of a double bar in this galaxy may present problems for our axisymmetric code., 15 pages, 21 figures, 13 tables. Accepted by ApJ
- Published
- 2009
46. Black Hole Outflows
- Author
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Andrew J. King
- Subjects
Physics ,Sphere of influence (black hole) ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,Astronomy and Astrophysics ,Quasar ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Accretion (astrophysics) ,Galaxy ,Black hole ,Interstellar medium ,symbols.namesake ,Space and Planetary Science ,Eddington luminosity ,symbols ,Astrophysics::Solar and Stellar Astrophysics ,Continuum (set theory) ,Astrophysics::Galaxy Astrophysics ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
I show that Eddington accretion episodes in AGN are likely to produce winds with velocities $v \sim 0.1c$ and ionization parameters up to $\xi \sim 10^4$ (cgs), implying the presence of resonance lines of helium-- and hydrogenlike iron. These properties are direct consequences of momentum and mass conservation respectively, and agree with recent X-ray observations of fast outflows from AGN. Because the wind is significantly subluminal, it can persist long after the AGN is observed to have become sub--Eddington. The wind creates a strong cooling shock as it interacts with the interstellar medium of the host galaxy, and this cooling region may be observable in an inverse Compton continuum and lower--excitation emission lines associated with lower velocities. The shell of matter swept up by the (`momentum--driven') shocked wind must propagate beyond the black hole's sphere of influence on a timescale $\la 3\times 10^5$ yr. Outside this radius the shell stalls unless the black hole mass has reached the value $M_{\sigma}$ implied by the $M - \sigma$ relation. If the wind shock did not cool, as suggested here, the resulting (`energy--driven') outflow would imply a far smaller SMBH mass than actually observed. In galaxies with large bulges the black hole may grow somewhat beyond this value, suggesting that the observed $M -\sigma$ relation may curve upwards at large $M$. Minor accretion events with small gas fractions can produce galaxy--wide outflows with velocities significantly exceeding $\sigma$, including fossil outflows in galaxies where there is little current AGN activity. Some rare cases may reveal the energy--driven outflows which sweep gas out of the galaxy and establish the black hole--bulge mass relation. However these require the quasar to be at the Eddington luminosity., Comment: MNRAS, to appear
- Published
- 2009
- Full Text
- View/download PDF
47. The mass of the black hole in Centaurus A from SINFONI AO-assisted integral-field observations of stellar kinematics
- Author
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P. van der Werf, Nadine Neumayer, H-W. Rix, Juha Reunanen, Michele Cappellari, and P. T. de Zeeuw
- Subjects
Physics ,Supermassive black hole ,Very Large Telescope ,Stellar kinematics ,Sphere of influence (black hole) ,Stellar rotation ,Centaurus A ,Astrophysics (astro-ph) ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Space and Planetary Science ,Elliptical galaxy ,Astrophysics::Solar and Stellar Astrophysics ,Surface brightness ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics::Galaxy Astrophysics - Abstract
We present a determination of the mass of the supermassive black hole (BH) and the nuclear stellar orbital distribution of the elliptical galaxy Centaurus A (NGC5128) using high-resolution integral-field observations of the stellar kinematics. The observations were obtained with SINFONI at the ESO Very Large Telescope in the near-infrared (K-band), using adaptive optics to correct for the blurring effect of the earth atmosphere. The data have a spatial resolution of 0.17" FWHM and high S/N>80 per spectral pixel so that the shape of the stellar line-of-sight velocity-distribution can be reliably extracted. We detect clear low-level stellar rotation, which is counter-rotating with respect to the gas. We fit axisymmetric three-integral dynamical models to the data to determine the best fitting values for the BH mass M_BH=(5.5+/-3.0)*10^7 Msun (3sigma errors) and (M/L)_K=(0.65+/-0.15) in solar units. These values are in excellent agreement with previous determinations from the gas kinematics, and in particular with our own published values, extracted from the same data. This provides one of the cleanest gas versus stars comparisons of BH determination, due to the use of integral-field data for both dynamical tracers and due to a very well resolved BH sphere of influence R_BH~0.70". We derive an accurate profile of the orbital anisotropy and we carefully test its reliability using spherical Jeans models with radially varying anisotropy. We find an increase in the tangential anisotropy close to the BH, but the spatial extent of this effect seems restricted to the size of R_BH instead of that R_b~3.9" of the core in the surface brightness profile, contrary to detailed predictions of current simulations of the binary BH scouring mechanism. More realistic simulations would be required to draw conclusions from this observation., 12 pages, 10 figures, LaTeX. Accepted for publication in MNRAS
- Published
- 2008
48. Deepest Near-IR Surface Photometry of Galaxies in the Local Sphere of Influence
- Author
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Stuart D. Ryder, Simon P. Driver, Emma Kirby, and Helmut Jerjen
- Subjects
Physics ,Surface (mathematics) ,Baryon ,Photometry (astronomy) ,Sphere of influence (black hole) ,Volume (thermodynamics) ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Astrophysics::Galaxy Astrophysics ,Galaxy - Abstract
We present near-IR, deep (4 mag deeper than 2MASS) imaging of 56 Local Volume galaxies. Global parameters such as total magnitudes and stellar masses have been derived and the new near-IR data combined with existing 21cm and optical B-band data. We present multiwavelength relations such as the HI mass-to-light ratio and investigate the maximum total baryonic mass a galaxy can have.
- Published
- 2008
- Full Text
- View/download PDF
49. Chavín de Huántar and Its Sphere of Influence
- Author
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Richard L. Burger
- Subjects
Geography ,Sphere of influence (black hole) ,Classical mechanics - Published
- 2008
- Full Text
- View/download PDF
50. The Black Hole Mass of NGC 4151: Comparison of Reverberation Mapping and Stellar Dynamical Measurements
- Author
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Christopher A. Onken, David Merritt, Ian M. McHardy, Richard W. Pogge, Sergey G. Sergeev, Timothy M. Heckman, Misty C. Bentz, Amri Wandel, Laura Ferrarese, Gary Bower, Monica Valluri, Marianne Vestergaard, D. Michael Crenshaw, and Bradley M. Peterson
- Subjects
Physics ,Sphere of influence (black hole) ,Line-of-sight ,010504 meteorology & atmospheric sciences ,Astrophysics::High Energy Astrophysical Phenomena ,Astrophysics (astro-ph) ,Rotational symmetry ,FOS: Physical sciences ,Sigma ,Astronomy and Astrophysics ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Galaxy ,Space and Planetary Science ,Bulge ,0103 physical sciences ,Reverberation mapping ,Astrophysics::Solar and Stellar Astrophysics ,Astrophysics::Earth and Planetary Astrophysics ,Disc ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,0105 earth and related environmental sciences - Abstract
We present a stellar dynamical estimate of the black hole (BH) mass in the Seyfert 1 galaxy, NGC 4151. We analyze ground-based spectroscopy as well as imaging data from the ground and space, and we construct 3-integral axisymmetric models in order to constrain the BH mass and mass-to-light ratio. The dynamical models depend on the assumed inclination of the kinematic symmetry axis of the stellar bulge. In the case where the bulge is assumed to be viewed edge-on, the kinematical data give only an upper limit to the mass of the BH of ~4e7 M_sun (1 sigma). If the bulge kinematic axis is assumed to have the same inclination as the symmetry axis of the large-scale galaxy disk (i.e., 23 degrees relative to the line of sight), a best-fit dynamical mass between 4-5e7 M_sun is obtained. However, because of the poor quality of the fit when the bulge is assumed to be inclined (as determined by the noisiness of the chi^2 surface and its minimum value), and because we lack spectroscopic data that clearly resolves the BH sphere of influence, we consider our measurements to be tentative estimates of the dynamical BH mass. With this preliminary result, NGC 4151 is now among the small sample of galaxies in which the BH mass has been constrained from two independent techniques, and the mass values we find for both bulge inclinations are in reasonable agreement with the recent estimate from reverberation mapping (4.57[+0.57/-0.47]e7 M_sun) published by Bentz et al., 20 pages, including 11 low-res figures. Accepted for publication in ApJ. High resolution version available upon request
- Published
- 2007
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