Navegação Ciências Exatas e da Terra por Assunto "Buracos negros"
Resultados 21-40 de 40
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Long-term profile variability in active galactic nucleus with double-peaked Balmer emission lines
(2010) [Artigo de periódico]An increasing number of active galactic nuclei (AGNs) exhibit broad, double-peaked Balmer emission lines, which represent some of the best evidence for the existence of relatively large-scale accretion disks in AGNs. A set ... -
A microquasar shot out from its birth place
(2004) [Artigo de periódico]We show that the microquasar LS I +61° 303 is running away from its birth place in a young complex of massive stars. The supernova explosion that formed the compact object shot out the X-ray binary with a linear momentum ... -
Models for jet power in elliptical galaxies : a case for rapidly spinning black holes
(2007) [Artigo de periódico]The power of jets from black holes is expected to depend on both the spin of the black hole and the structure of the accretion disc in the region of the last stable orbit.We investigate these dependencies using two different ... -
Nuclear spirals as feeding channels to the supermassive black hole : the case of the galaxy NGC 6951
(2007) [Artigo de periódico]We report the discovery of gas streaming motions along nuclear spiral arms toward the LINER nucleus of the galaxyNGC 6951. The observations, obtained using theGMOS integral field spectrograph on the Gemini North telescope, ... -
On the black hole mass of the γ-ray emitting narrow-line Seyfert 1 galaxy 1H 0323+342
(2017) [Artigo de periódico]Narrow-line Seyfert 1 galaxies have been identified by the Fermi Gamma-Ray Space Telescope as a rare class of γ -ray emitting active galactic nuclei. The lowest redshift candidate among them is the source 1H 0323+342. Here ... -
Quasinormal modes and stability of accelerating Reissner-Norsdtröm AdS black holes
(2022) [Artigo de periódico]We investigate the numerical stability of accelerating AdS black holes against linear scalar perturbations. In particular, we study the evolution of a probe non-minimally coupled scalar field on Schwarzschild and ... -
Radiatively inefficient accretion flow in the nucleus of NGC 1097
(2006) [Artigo de periódico]We present a model for the accretion flow around the supermassive black hole in the LINER nucleus of NGC 1097 that fits the optical to X-ray spectral energy distribution (SED). The X-ray segment of the SED is based on ... -
Short timescale variations of the Hα double-peaked profile of the nucleus of NGC 1097
(2012) [Artigo de periódico]The broad (FWHM ∼ 10,000 km s-ˡ) double-peaked Hα profile from the LINER/Seyfert 1 nucleus of NGC 1097 was discovered in 1991 and monitored for the following 11 years. The profile showed variations attributed to the rotation ... -
A snapshot of the continuous emission of the active galactic nucleus in ngc 3783 from gamma-ray to radio wavelengths
(1995) [Artigo de periódico]With the aim of better understanding the physical processes that produce the continuous emission in active galactic nuclei (AGNs), a snapshot of the overall continuous energy distribution of NGC 3783, from γ-ray to radio ... -
Spectral models for low-luminosity active galactic nuclei in LINERs : the role of advection-dominated accretion and jets
(2014) [Artigo de periódico]We find evidence for a correlation between the accretion rate and jet power and an anticorrelation between the radio loudness and the accretion rate.We confirm previous findings that the radio emission is severely ... -
Streaming motions toward the supermassive black hole in NGC 1097
(2006) [Artigo de periódico]We have used GMOS-IFU and high-resolution HST-ACS observations to map, in unprecedented detail, the gas velocity field and structure within the 0.7 kpc circumnuclear ring of the SBb LINER/Seyfert 1 galaxy NGC 1097.We find ... -
A strong correlation between circumnuclear dust and black hole accretion in early-type galaxies
(2007) [Artigo de periódico]We present a detailed investigation of the incidence of circumnuclear dust structure in a large, well-matched sample of early-type galaxies with and without active galactic nuclei (AGNs). All 34 early-type AGN hosts in our ... -
The benchmark black hole in NGC 4258 : dynamical models from high-resolution two-dimensional stellar kinematics
(2015) [Artigo de periódico]NGC 4258 is the galaxy with the most accurate (maser-based) determination for the mass of the supermassive black hole (SMBH) in its nucleus. In this work, we present a two-dimensional mapping of the stellar kinematics in ... -
The black hole mass of NGC 4151. II. Stellar dynamical measurement from near-infrared field spectroscopy
(2014) [Artigo de periódico]We present a revised measurement of themass of the central black hole (MBH ) in the Seyfert 1 galaxyNGC4151. The new stellar dynamical mass measurement is derived by applying an axisymmetric orbit-superposition code to ... -
The complex gas kinematics in the nucleus of the Seyfert 2 galaxy NGC 1386 : rotation, outflows, and inflows
(2015) [Artigo de periódico]We present optical integral field spectroscopy of the circum-nuclear gas of the Seyfert 2 galaxy NGC 1386. The data cover the central 7″ × 9″ (530 × 680 pc) at a spatial resolution of 0″. 9 (68 pc), and the spectral range ... -
The complex jet- and bar- perturbed kinematics in NGC 3393 as revealed with ALMA and GEMINI–GMOS/IFU
(2018) [Artigo de periódico]NGC 3393, a nearby Seyfert 2 galaxy with nuclear radio jets, large-scale and nuclear bars, and a posited secondary supermassive black hole, provides an interesting laboratory to test the physics of inflows and outflows. ... -
The Gemini spectral library of near-ir late-type stellar templates and its application for velocity dispersion measurements
(2009) [Artigo de periódico]We present a spectroscopic library of late spectral type stellar templates in the near-IR range 2.15–2.42 μm, at R = 5300–5900 resolution, oriented to support stellar kinematics studies in external galaxies, such as the ... -
The missing goliath's slingshot : massive black hole recoil at M83
(2010) [Artigo de periódico]The Fanaroff–Riley II radio source J133658.3−295105, which is also an X-ray source, appears to be projected onto the disk of the barred-spiral galaxy M83 at about 60" from the galaxy’s optical nucleus. J133658.3−295105 and ... -
The origin of dust in early-type galaxies and implications for accretion onto supermassive black holes
(2013) [Artigo de periódico]We have conducted an archival Spitzer study of 38 early-type galaxies in order to determine the origin of the dust in approximately half of this population. Our sample galaxies generally have good wavelength coverage from ... -
The role of host galaxy for the environmental dependence of active nuclei in local galaxies
(2017) [Artigo de periódico]We discuss the environment of local hard X-ray selected active galaxies, with reference to two independent group catalogues. We find that the fraction of these AGN in S0 host galaxies decreases strongly as a function of ...
