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Title: Vertical Structure of Radiation-pressure-dominated Thin Disks: Link between Vertical Advection and Convective Stability

Abstract

In the classic picture of standard thin accretion disks, viscous heating is balanced by radiative cooling through the diffusion process, and the radiation-pressure-dominated inner disk suffers convective instability. However, recent simulations have shown that, owing to the magnetic buoyancy, the vertical advection process can significantly contribute to energy transport. In addition, in comparing the simulation results with the local convective stability criterion, no convective instability has been found. In this work, following on from simulations, we revisit the vertical structure of radiation-pressure-dominated thin disks and include the vertical advection process. Our study indicates a link between the additional energy transport and the convectively stable property. Thus, the vertical advection not only significantly contributes to the energy transport, but it also plays an important role in making the disk convectively stable. Our analyses may help to explain the discrepancy between classic theory and simulations on standard thin disks.

Authors:
;  [1]
  1. Department of Astronomy, Xiamen University, Xiamen, Fujian 361005 (China)
Publication Date:
OSTI Identifier:
22663684
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 839; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCRETION DISKS; ADVECTION; BLACK HOLES; CONVECTION; CONVECTIVE INSTABILITIES; DIFFUSION; POWER TRANSMISSION; RADIATION PRESSURE; RADIATIVE COOLING; SIMULATION; STABILITY

Citation Formats

Gong, Hong-Yu, and Gu, Wei-Min, E-mail: guwm@xmu.edu.cn. Vertical Structure of Radiation-pressure-dominated Thin Disks: Link between Vertical Advection and Convective Stability. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA6976.
Gong, Hong-Yu, & Gu, Wei-Min, E-mail: guwm@xmu.edu.cn. Vertical Structure of Radiation-pressure-dominated Thin Disks: Link between Vertical Advection and Convective Stability. United States. doi:10.3847/1538-4357/AA6976.
Gong, Hong-Yu, and Gu, Wei-Min, E-mail: guwm@xmu.edu.cn. Thu . "Vertical Structure of Radiation-pressure-dominated Thin Disks: Link between Vertical Advection and Convective Stability". United States. doi:10.3847/1538-4357/AA6976.
@article{osti_22663684,
title = {Vertical Structure of Radiation-pressure-dominated Thin Disks: Link between Vertical Advection and Convective Stability},
author = {Gong, Hong-Yu and Gu, Wei-Min, E-mail: guwm@xmu.edu.cn},
abstractNote = {In the classic picture of standard thin accretion disks, viscous heating is balanced by radiative cooling through the diffusion process, and the radiation-pressure-dominated inner disk suffers convective instability. However, recent simulations have shown that, owing to the magnetic buoyancy, the vertical advection process can significantly contribute to energy transport. In addition, in comparing the simulation results with the local convective stability criterion, no convective instability has been found. In this work, following on from simulations, we revisit the vertical structure of radiation-pressure-dominated thin disks and include the vertical advection process. Our study indicates a link between the additional energy transport and the convectively stable property. Thus, the vertical advection not only significantly contributes to the energy transport, but it also plays an important role in making the disk convectively stable. Our analyses may help to explain the discrepancy between classic theory and simulations on standard thin disks.},
doi = {10.3847/1538-4357/AA6976},
journal = {Astrophysical Journal},
number = 2,
volume = 839,
place = {United States},
year = {Thu Apr 20 00:00:00 EDT 2017},
month = {Thu Apr 20 00:00:00 EDT 2017}
}
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