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 ms.tex ApJ, Apr 2006, submitted
X-Spam-Status: No

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%http://www.arxiv.org/abs/astro-ph/0604509

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\shorttitle{Hot Accretion With Outflows}
\shortauthors{Tanaka \& Menou}

\begin{document}

\title{Hot Accretion With Conduction: Spontaneous Thermal Outflows}

\author{Takamitsu Tanaka}
\affil{Department of Astronomy, Columbia University, 550 West
120th Street, New York, NY 10027}
\author{Kristen Menou}
\affil{Department of Astronomy, Columbia University, 550 West
120th Street, New York, NY 10027}



\begin{abstract}
Motivated by the low-collisionality of gas accreted onto black holes
in Sgr~A* and other nearby galactic nuclei, we study a family of 2D
advective accretion solutions with thermal conduction. While we only
impose global inflow, the accretion flow spontaneously develops
bipolar outflows. The role of conduction is key in providing the extra
degree of freedom (latitudinal energy transport) necessary to launch
these rotating thermal outflows.  The sign of the Bernoulli constant
does not discriminate between inflowing and outflowing regions. Our
parameter survey covers mass outflow rates from $\sim 0$ to $13\%$ of
the net inflow rate, outflow velocities from $\sim 0$ to $11\%$ of the
local Keplerian velocity and outflow opening angles from $\sim 0$ to $
60$~degs.  As the magnitude of conduction is increased, outflows can
adopt a conical geometry, pure inflow solutions emerge, and the limit
of 2D non-rotating Bondi-like solutions is eventually reached.  These
results confirm that radiatively-inefficient, hot accretion flows have
a hydrodynamical propensity to generate bipolar thermal outflows.
\end{abstract}

\keywords{accretion, accretion disks -- conduction -- black hole
physics -- hydrodynamics}


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