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Related papers: Long-Lived Eccentricities in Accretion Disks

200 papers

Magnetic connections to the plunging region can exert stresses on the inner edge of an accretion disk around a black hole. We recompute the relativistic corrections to the thin-disk dynamics equations when these stresses take the form of a…

Astrophysics · Physics 2009-10-31 Eric Agol , Julian Krolik

We study a truncated accretion disk using a well-resolved, semi-global magnetohydrodynamic simulation that is evolved for many dynamical times (6096 inner disk orbits). The spectral properties of hard state black hole binary systems and…

High Energy Astrophysical Phenomena · Physics 2018-04-25 J. Drew Hogg , Christopher S. Reynolds

We have applied an eccentric accretion disc theory in simplified form to the case of an accretion disc in a binary system, where the disc contains the 3:1 Lindblad resonance. This is relevant to the case of superhumps in SU Ursae Majoris…

Astrophysics · Physics 2009-11-11 Simon Goodchild , Gordon Ogilvie

Although the occurrence of steady supercritical disk accretion onto a black hole has been speculated about since the 1970s, it has not been accurately verified so far. For the first time, we previously demonstrated it through…

Astrophysics · Physics 2009-11-13 Ken Ohsuga , Shin Mineshige

Accretion discs are fundamental to many astrophysical systems, providing the conversion of gravitational potential energy into radiation that we can observe. In many systems there is evidence that discs are warped; from spatially-resolved…

High Energy Astrophysical Phenomena · Physics 2026-05-05 Chris Nixon , Jim Pringle

We construct Super-Eddington Slim Disks models around both stellar and super-massive black holes by allowing the formation of a porous layer with a reduced effective opacity. We show that at high accretion rates, the inner part of the disks…

High Energy Astrophysical Phenomena · Physics 2015-05-18 Calanit Dotan , Nir J. Shaviv

Numerical hydrodynamics calculations are performed to determine conditions under which giant planet eccentricities can be excited by parent gas disks. Unlike in other studies, Jupiter-mass planets are found to have their eccentricities…

Earth and Planetary Astrophysics · Physics 2015-10-21 Paul C. Duffell , Eugene Chiang

We associate the existence of short-lived compact radio sources with the intermittent activity of the central engine caused by a radiation pressure instability within an accretion disk. Such objects may constitute a numerous sub-class of…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-11 Bozena Czerny , Aneta Siemiginowska , Agnieszka Janiuk , Blazej Nikiel-Wroczynski , Lukasz Stawarz

Standard accretion disk theory is formulated which is based on the local heat balance. The energy produced by a turbulent viscous heating is supposed to be emitted to the sides of the disc. Sources of turbulence in the accretion disc are…

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

The viscous evolution of a thin disc around a central object is considered. Such discs are described by self-similar solutions in which either all or none of the inflowing mass accretes. An approximate solution for the partial accretion…

High Energy Astrophysical Phenomena · Physics 2012-10-22 K. Yavuz Ekşi

This review covers the main aspects of black hole accretion disk theory. We begin with the view that one of the main goals of the theory is to better understand the nature of black holes themselves. In this light we discuss how accretion…

High Energy Astrophysical Phenomena · Physics 2015-05-28 Marek A. Abramowicz , P. Chris Fragile

Disk accretion onto a weakly magnetized central object, e.g. a star, is inevitably accompanied by the formation of a boundary layer near the surface, in which matter slows down from the highly supersonic orbital velocity of the disk to the…

Solar and Stellar Astrophysics · Physics 2015-06-05 Mikhail A. Belyaev , Roman R. Rafikov , James M. Stone

We use global magnetohydrodynamic simulations to study the influence of net vertical magnetic fields on the structure of geometrically thin ($H/r \approx 0.05$) accretion disks in the Newtonian limit. We consider initial mid-plane gas to…

High Energy Astrophysical Phenomena · Physics 2020-01-23 Bhupendra Mishra , Mitchell C. Begelman , Philip J. Armitage , Jacob B. Simon

Observations of exoplanets have revealed that systems with planets on closely-spaced orbits are common, which motivates the question "How closely can planets orbit to one another and still be dynamically-stable for very long times?". To…

Earth and Planetary Astrophysics · Physics 2020-07-28 Pierre Gratia , Jack J. Lissauer

Accretion discs properties should deviate from standard theory when magnetic pressure exceeds the thermal pressure. To quantify these deviations, we present a systematic study of the dynamical properties of magnetically arrested discs…

High Energy Astrophysical Phenomena · Physics 2023-10-26 Nicolas Scepi , Mitchell C. Begelman , Jason Dexter

Eccentric disks arise in such astrophysical contexts as tidal disruption events, but it is unknown whether the magnetorotational instability (MRI), which powers accretion in circular disks, operates in eccentric disks as well. We examine…

High Energy Astrophysical Phenomena · Physics 2020-01-24 Chi-Ho Chan , Julian H. Krolik , Tsvi Piran

We demonstrate that generically an accretion disk around a compact object could have a new type of instability in that the accretion flow need not be symmetric with respect to the equatorial plane even when matter is supplied symmetrically…

Astrophysics · Physics 2015-06-24 D. Molteni , K. Acharya , Oleg Kuznetsov , D. Bisikalo , Sandip K. Chakrabarti

Two-dimensional accretion flows near black holes have been investigated by time-dependent hydrodynamical calculations. We assume that the flow is axisymmetric and that radiative losses of internal energy are negligible, so that the disc is…

Astrophysics · Physics 2015-06-24 Igor V. Igumenshchev , Xingming Chen , Marek A. Abramowicz

Models of black hole accretion disks are reviewed, with an emphasis on the theory of hard X-ray production. The following models are considered: i) standard, ii) super-critical, iii) two-temperature, and iv) disk+corona. New developments…

Astrophysics · Physics 2007-05-23 Andrei M. Beloborodov

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