Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Viscosity parameter in dissipative accretion flows with mass outflow
  around black holes   Numerical hydrodynamic simulation of inviscid and viscous flows have shown
that significant outflows could be produced from the CENtrifugal pressure
supported BOundary Layer or CENBOL of an advective disk. However, this barrier
is weakened in presence of viscosity, more so, if there are explicit energy
dissipations at the boundary layer itself. We study effects of viscosity and
energy dissipation theoretically on the outflow rate and show that as the
viscosity or energy dissipation (or both) rises, the prospect of formation of
outflows is greatly reduced, thereby verifying results obtained through
observations and numerical simulations. Indeed, we find that in a dissipative
viscous flow, shocks in presence of outflows can be produced only if the
Shakura-Sunyaev viscosity parameter {\alpha} is less than 0.2. This is a direct
consequence of modification of the Rankine-Hugoniot relation across the shock
in a viscous flow, when the energy dissipation and mass loss in the form of
outflows from the post-shock region are included. If we ignore the effects of
mass loss altogether, the standing dissipative shocks in viscous flows may
occur only if {\alpha} < 0.27. These limits are tighter than the absolute limit
of {\alpha} = 0.3 valid for a situation when the shock itself neither
dissipates energy nor any outflow is formed. We compute typical viscosity
parameters required to understand spectral and temporal properties of several
black hole candidates such as GX399-4, MAXI J1659-152 and MAXI J1836-194 and
find that required {\alpha} are indeed well within our prescribed limit.

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The categories of this paper are: nucl-ex
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The categories of this paper are: eess
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The categories of this paper are: cs
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The categories of this paper are: q-alg
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The categories of this paper are: chem-ph
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The categories of this paper are: econ
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The categories of this paper are: cond-mat
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The categories of this paper are: atom-ph
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The categories of this paper are: math-ph
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The categories of this paper are: solv-int
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The categories of this paper are: comp-gas
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The categories of this paper are: gr-qc
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The categories of this paper are: funct-an
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The categories of this paper are: nlin
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The categories of this paper are: q-fin
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The categories of this paper are: nucl-th