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Related papers: Hypercritical Advection Dominated Accretion Flow

200 papers

We formulate the problem of the late accretion phase of the evolution of an isothermal magnetic disk surrounding a forming star. The evolution is described by the six-fluid MHD equations, accounting for the presence of neutrals, atomic and…

Astrophysics · Physics 2009-11-10 Konstantinos Tassis , Telemachos Ch. Mouschovias

We present the results from axisymmetric time-dependent HD calculations of gas flows which are under the influence of gravity of a black hole in quasars. We assume that the flows are non-rotating and exposed to quasar radiation. We take…

Astrophysics · Physics 2011-02-11 Daniel Proga

Accretion disks formed in binary neutron star mergers play a central role in many astrophysical processes of interest, including the launching of relativistic jets or the ejection of neutron-rich matter hosting heavy element…

High Energy Astrophysical Phenomena · Physics 2024-03-19 Alessandro Camilletti , Albino Perego , Federico Maria Guercilena , Sebastiano Bernuzzi , David Radice

We have developed a three-dimensional numerical model and applied it to simulate plasma flows in semi-detached binary systems whose accretor possesses a strong intrinsic magnetic field. The model is based on the assumption that the plasma…

Solar and Stellar Astrophysics · Physics 2010-10-26 A. G. Zhilkin , D. V. Bisikalo

Understanding how accretion proceeds in proto-planetary discs and more generally their dynamics is a crucial issue for explaining the conditions in which planets form. The role that accretion of gas from the surrounding molecular cloud onto…

Astrophysics of Galaxies · Physics 2017-03-15 Patrick Hennebelle , Geoffroy Lesur , Sébastien Fromang

In many cases accretion proceeds from disks onto planets, stars, white dwarfs, and neutron stars via a boundary layer, a region of intense shear where gas transitions from a near-Keplerian speed to that of the surface. These regions are…

High Energy Astrophysical Phenomena · Physics 2024-06-03 Alexander J. Dittmann

All high temperature accretion solutions including ADAF are physically thick, so outgoing radiation interacts with the incoming flow, sharing as much or more resemblance with classical spherical accretion flows as with disk flows. We…

Astrophysics · Physics 2009-10-31 Myeong-Gu Park , Jeremiah P. Ostriker

Accretion disks are observed in young stars, cataclysmic variables, binary X-ray sources et al. Accretion disk theory was first developed as a theory with the local heat balance, where the whole energy produced by a viscous heating was…

Astrophysics · Physics 2007-05-23 G. S. Bisnovatyi-Kogan

Before a binary system enters into a common envelope (CE) phase, accretion from the primary star onto the companion star through Roche Lobe overflow (RLOF) will lead to the formation of an accretion disk, which may generate jets. Accretion…

We investigate the atmosphere, ocean, and crust of neutron stars accreting at rates sufficiently high (typically in excess of the local Eddington limit) to stabilize the burning of accreted hydrogen and helium. For hydrogen-rich accretion…

Astrophysics · Physics 2009-10-30 Edward F. Brown , Lars Bildsten

Nuclear reactions occurring deep in the crust of a transiently accreting neutron star efficiently maintain the core at a temperature >5e7 K. When accretion halts, the envelope relaxes to a thermal equilibrium set by the flux from the hot…

Astrophysics · Physics 2009-10-30 Edward F. Brown , Lars Bildsten , Robert E. Rutledge

We study the accretion on to the neutron star in Be/X-ray binaries, using a 3D SPH code and the data imported from a simulation by \citet{oka2} for a coplanar system with a short period ($P_{\rm orb}=24.3 \rm{d}$) and a moderate…

Astrophysics · Physics 2009-11-10 Kimitake Hayasaki , Atsuo T. Okazaki

We consider the effects of advection and radial gradients of pressure and radial drift velocity on the structure of accretion disks around black holes with proper description of optically thick/thin transitions. We concentrated our efforts…

Astrophysics · Physics 2009-11-10 Yu. V. Artemova , G. S. Bisnovatyi-Kogan , I. V. Igumenshchev , I. D. Novikov

We investigated a semi-analytic and numerical model to study the geometrically thin and optically thick accretion disk around Maclaurin spheroid (MS). The main interest is in the inner region of the so called {\alpha}-disk, {\alpha} being…

High Energy Astrophysical Phenomena · Physics 2015-06-23 B. Mishra , B. Vaidya

Outflows are inevitably driven from the disk if the vertical component of the black hole (BH) gravity cannot resist the radiation force. We derive the mass loss rate in the outflows by solving a dynamical equation for the vertical gas…

High Energy Astrophysical Phenomena · Physics 2022-09-21 Xinwu Cao , Wei-Min Gu

We model the UV/optical spectrum of the black hole binary Nova Muscae as a sum of black body emissions from the outer region of an accretion disk. We show for self-consistency that scattering effects in this region are not important. The…

Astrophysics · Physics 2009-10-30 Ranjeev Misra

We study the observational signatures from the interactions between a newly born neutron star and a companion star that is impacted by the supernova ejecta. We focus on the cases with bound post-explosion orbits, where the neutron star may…

High Energy Astrophysical Phenomena · Physics 2025-07-22 Wenbin Lu , Savannah Cary , Daichi Tsuna

X-ray observations of the tidal disruption event (TDE) candidate AT 2019avd show drastic variabilities in flux and spectral shape over hundreds of days, providing clues on the accretion disc-corona evolution. We utilize a disc-corona model,…

High Energy Astrophysical Phenomena · Physics 2026-03-27 Haichao Xu , Xinwu Cao , Yanan Wang , Andrzej A. Zdziarski

Observations indicate that stars generally lose their protoplanetary discs on a timescale of about 5 Myr. Which mechanisms are responsible for the disc dissipation is still debated. Here we investigate the movement through an ambient medium…

Solar and Stellar Astrophysics · Physics 2017-06-21 T. P. G. Wijnen , O. R. Pols , F. I. Pelupessy , S. Portegies Zwart

It is commonly believed that accretion discs are truncated and their inner regions are described by advection dominated accretion flows (ADAFs) in the hard spectral state of black hole X-ray binaries. However, the increasing occurrence of a…

High Energy Astrophysical Phenomena · Physics 2023-11-09 Yilong Wang , Bifang Liu , Erlin Qiao , Huaqing Cheng