English
Related papers

Related papers: Eccentric-disk models for the nucleus of M31

200 papers

The observation of gravitational waves from merging black holes and neutron stars provides a unique opportunity to discern information about their astrophysical environment. Two signatures that are considered powerful tracers to distinguish…

High Energy Astrophysical Phenomena · Physics 2026-03-18 Gonzalo Morras , Geraint Pratten , Patricia Schmidt

We perform force-free simulations for a neutron star orbiting a black hole, aiming at clarifying the main magnetosphere properties of such binaries towards their innermost stable circular orbits. Several configurations are explored, varying…

High Energy Astrophysical Phenomena · Physics 2021-09-08 Federico Carrasco , Masaru Shibata , Oscar Reula

Circumstellar disks are characteristic for star formation and vanish during the first few Myr of stellar evolution. During this time planets are believed to form in the dense midplane by growth, sedimentation and aggregation of dust.…

Solar and Stellar Astrophysics · Physics 2015-06-05 D. Madlener , S. Wolf , A. Dutrey , S. Guilloteau

It is usually thought that viscous torque works to align a circumbinary disk with the binary's orbital plane. However, recent numerical simulations suggest that the disk may evolve to a configuration perpendicular to the binary orbit…

Earth and Planetary Astrophysics · Physics 2017-10-11 J. J. Zanazzi , Dong Lai

We present a reanalysis of the EHT 228 GHz observations of M87. We apply traditional hybrid mapping techniques to the publicly available `network-calibrated' data. We explore the impact on the final image of different starting models,…

Cosmology and Nongalactic Astrophysics · Physics 2022-01-26 Christopher L. Carilli , Nithyanandan Thyagarajan

Compact binaries on eccentric orbits are another class of gravitational-wave (GW) sources that can provide a wealth of information on binary formation pathways and astrophysical environments. However, historically, eccentricity is often…

General Relativity and Quantum Cosmology · Physics 2025-02-19 Khun Sang Phukon , Patricia Schmidt , Geraint Pratten

We review some of the interesting consequences that tilts, warps, and eccentricities can introduce into the dynamics, thermodynamics, and observational appearance of accreting systems, with an emphasis on disks around black holes and…

High Energy Astrophysical Phenomena · Physics 2026-03-04 P. Chris Fragile , Adam Ingram , Gibwa Musoke , Gordon I. Ogilvie

This paper focuses on the dynamical implications of close supermassive black hole binaries both as an example of resonant phase mixing and as a potential explanation of inversions and other anomalous features observed in the luminosity…

Astrophysics · Physics 2009-11-07 Henry E. Kandrup , Ioannis V. Sideris , Balsa Terzic , Courtlandt L. Bohn

We study the dynamics of a star orbiting a merging black-hole binary (BHB) in a coplanar triple configuration. During the BHB's orbital decay, the system can be driven across the apsidal precession resonance, where the apsidal precession…

High Energy Astrophysical Phenomena · Physics 2024-06-10 Bin Liu , Dong Lai

The Event Horizon Telescope (EHT) has produced images of two supermassive black holes, Messier~87* (M 87*) and Sagittarius~A* (Sgr A*). The EHT collaboration used these images to indirectly constrain black hole parameters by calibrating…

High Energy Astrophysical Phenomena · Physics 2022-11-30 Daniel C. M Palumbo , Zachary Gelles , Paul Tiede , Dominic O. Chang , Dominic W. Pesce , Andrew Chael , Michael D. Johnson

This paper has been withdrawn temporarily by the authors. As stars close to the galactic centre have short orbital periods it has been possible to trace large fractions of their orbits in the recent years. Previously the data of the orbit…

Astrophysics · Physics 2009-11-10 N. Mouawad , A. Eckart , S. Pfalzner , R. Schoedel , J. Moultaka , R. Spurzem

Hypervelocity stars (HVSs) that are observed in the Galactic halo, are believed to be accelerated to large velocities by a process of tidal disruption of binary stars passing close to a supermassive black hole (SMBH) which resides in the…

Astrophysics of Galaxies · Physics 2016-09-28 Ladislav Subr , Jaroslav Haas

We review the current state of dynamical modeling for galaxies in terms of being able to measure both the central black hole mass and stellar orbital structure. Both of these must be known adequately to measure either property. The current…

Astrophysics · Physics 2007-05-23 Karl Gebhardt

We combine Hubble Space Telescope spectroscopy and ground-based integral-field data from the SAURON and OASIS instruments to study the central black hole in the nearby elliptical galaxy NGC 3379. From these data, we obtain kinematics of…

We present long-slit HST/STIS measurements of the ionized-gas kinematics in the nucleus of three disk galaxies, namely NGC 2179, NGC 4343, NGC 4435. The sample galaxies have been selected on the basis of their ground-based spectroscopy, for…

Astrophysics · Physics 2009-11-10 L. Coccato , E. Dalla Bonta' , M. Sarzi , A. Pizzella , E. M. Corsini , F. Bertola

We analyze the structural parameters of the largest-available sample of spatially resolved extragalactic globular clusters. The images of M31 GCs were found in a search of HST archival data, described in a companion paper. We measure the…

Astrophysics · Physics 2007-05-23 P. Barmby , S. Holland , J. P. Huchra

We have developed a set of dynamically evolving Fokker-Planck models for the collapsed-core globular star cluster M15, which directly address the issue of whether a central black hole is required to fit Hubble Space Telescope (HST)…

Astrophysics of Galaxies · Physics 2012-05-07 Brian W. Murphy , Haldan N. Cohn , Phyllis M. Lugger

We investigate the orbital eccentricity evolution of supermassive black hole binaries within galactic environments. We analyze the dynamics in triaxial merger remnants and subsequent interactions with geometrically thick nuclear discs. We…

We fit axisymmetric 3-integral dynamical models to NGC3379 using the line-of-sight velocity distribution obtained from HST/FOS spectra of the galaxy center and ground-based long-slit spectroscopy along four position angles, with the light…

We describe a novel framework to model galaxy spectra with two cospatial stellar populations, such as may represent a bulge & bar or thick & thin disc, and apply it to APOGEE spectra in the inner $\sim$2 kpc of M31, as well as to stacked…