English
Related papers

Related papers: Modified Slim-Disk Model Based on Radiation-Hydrod…

200 papers

To what extent can the one-dimensional slim disk model reproduce the multi-dimensional results of global radiation-hydrodynamic simulations of super-Eddington accretion? With this question in mind, we perform systematic simulation study of…

High Energy Astrophysical Phenomena · Physics 2018-11-07 Takaaki Kitaki , Shin Mineshige , Ken Ohsuga , Tomohisa Kawashima

Photon trapping is believed to be an important mechanism in super-Eddington accretion, which greatly reduces the radiative efficiency as photons are swallowed by the central black hole before they can escape from the accretion flow. This…

High Energy Astrophysical Phenomena · Physics 2023-08-17 Cheng-Liang Jiao

The quasi-steady structure of super-critical accretion flows around a black hole is studied based on the two-dimensional radiation-hydrodynamical (2D-RHD) simulations. The super-critical flow is composed of two parts: the disk region and…

Astrophysics · Physics 2009-11-10 K. Ohsuga , M. Mori , T. Nakamoto , S. Mineshige

By performing 2.5-dimensional special relativistic radiation magnetohydrodynamics simulations, we study the super-critical accretion disks and the outflows launched via the radiation force. We find that the outflow is accelerated by the…

High Energy Astrophysical Phenomena · Physics 2015-06-23 Hiroyuki R. Takahashi , Ken Ohsuga

In order to understand the physical processes underlying clump formation in outflow from supercritical accretion flow, we performed two-dimensional radiation hydrodynamic (RHD) simulations. We focus our discussion on the nature of RHD…

High Energy Astrophysical Phenomena · Physics 2015-06-18 S. Takeuchi , K. Ohsuga , S. Mineshige

We investigate the photon-trapping effects in the super-critical black hole accretion flows by solving radiation transfer as well as the energy equations of radiation and gas. It is found that the slim-disk model generally overestimates the…

Astrophysics · Physics 2009-11-07 Ken Ohsuga , Shin Mineshige , Masao Mori , Masayuki Umemura

The thickness of a slim disk is determined by the balance between the radiation force and the vertical component of the gravity of the black hole (BH). It was found that vertical gravity increases with the disk height, and it will decrease…

High Energy Astrophysical Phenomena · Physics 2019-12-04 Junjie Feng , Xinwu Cao , Wei-Min Gu , Ren-Yi Ma

We study the dynamics of super-Eddington accretion flows by performing two-dimensional radiation-hydrodynamic simulations. Compared with previous works, in this paper we include the $T_{\theta\phi}$ component of the viscous stress and…

High Energy Astrophysical Phenomena · Physics 2015-06-16 Xiao-Hong Yang , Feng Yuan , Ken Ohsuga , De-Fu Bu

A widely accepted picture of an accretion flow in the luminous soft spectral state of X-ray binary systems is a geometrically thin disc structure much like the classic analytic solution of Shakura \& Sunyaev. Although the analytic models…

The supercritical disk accretion flow with radiatively driven outflows is studied based on two-dimensional radiation-hydrodynamic simulations for a wide range of the mass input rate, $\dot{M}_{\rm input}$, which is the mass supplied from…

Astrophysics · Physics 2011-02-11 K. Ohsuga

We present the detailed global structure of black hole accretion flows and outflows through newly performed two-dimensional radiation-magnetohydrodynamic simulations. By starting from a torus threaded with weak toroidal magnetic fields and…

High Energy Astrophysical Phenomena · Physics 2015-05-28 Ken Ohsuga , Shin Mineshige

Observed IR excesses indicate that protoplanetary discs evolve slowly for the majority of their lifetime before losing their near- and mid-IR excesses on short timescales. Photoevaporation models can explain this "two-timescale" nature of…

Earth and Planetary Astrophysics · Physics 2024-12-09 Alfie Robinson , James E. Owen , Richard A. Booth

Black-hole accretion systems are known to possess several distinct modes (or spectral states), such as low/hard state, high/soft state, and so on. Since the dynamics of the corresponding flows is distinct, theoretical models were separately…

High Energy Astrophysical Phenomena · Physics 2015-05-13 Ken Ohsuga , Shin Mineshige , Masao Mori , Yoshiaki Kato

We solve the radiation-hydrodynamic (RHD) equations of supercritical accretion flows in the presence of radiation force and outflow by using self similar solutions. Compare with the pioneer works, in this paper we consider power-law…

High Energy Astrophysical Phenomena · Physics 2016-06-01 Fatemeh Zahra Zeraatgari , Shahram Abbassi , Amin Mosallanezhad

We present a set of four three-dimensional, general relativistic, radiation MHD simulations of black hole accretion at super-critical mass accretion rates, $\dot{M} > \dot{M}_{\rm Edd}$. We use these simulations to study how disk properties…

High Energy Astrophysical Phenomena · Physics 2016-01-20 Aleksander Sadowski , Ramesh Narayan

We use hydrodynamic simulations to provide quantitative estimates of the effects of the impact of the accretion stream on disks in interacting binaries. For low accretion rates, efficient radiative cooling of the hotspot region can occur,…

Astrophysics · Physics 2016-08-30 Philip J. Armitage , Mario Livio

The photoevaporation of protoplanetary discs by nearby massive stars present in their birth cluster plays a vital role in their evolution. Previous modelling assumes that the disc behaves like a classical Keplerian accretion disc out to a…

Earth and Planetary Astrophysics · Physics 2021-10-27 James E Owen , Noumahn Altaf

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

In this chapter, we summarize recent progress on the properties of accretion disks when the accretion rate exceeds the so-called Eddington limit based on multi-dimensional radiation magnetohydrodynamic simulations. We first summarize the…

High Energy Astrophysical Phenomena · Physics 2024-09-02 Yan-Fei Jiang , Lixin Dai

We performed two-dimensional radiation hydrodynamic simulations of supercritical accretion flows around neutron stars (NSs). In contrast with the accretion flows onto black holes (BHs), we find that the shell-shaped high-density regions…

Astrophysics · Physics 2015-05-13 Ken Ohsuga
‹ Prev 1 2 3 10 Next ›