Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Application of MHD Disk Wind Solutions to Planetary/Protoplanetary
  Nebulae   Winds from accretion disks have been proposed as the driving source for
precessing jets and extreme bipolar morphologies in Planetary Nebulae (PNe) and
proto-PNe (pPNe). In this paper we address the applicability MHD disk wind
models to PNe and pPNe. We first review Pelletier & Pudritz's (1992) non
self-similar approach to magneto-centrifugal disk winds. We then discuss
conditions which may occur in PNe and pPNe accretion disks that form via binary
interactions. Finally, examining conditions on dimensionless parameters needed
for the magneto-centrifugal disk wind model, we show that such winds can
recover the observed momentum and energy input rates for PNe and pPNe. High
accretion rates ($M_a \approx 10^{-4}$ \mdot) may be required in the latter
case. We find that the observed {\it total} energy and momentum in pPNe can be
recovered with disk wind models using existing disk formation scenarios. When
combined with existing scenarios for accretion disk formation from disrupted
stellar companions, our models may provide an explanation for the existence of
high speed polar knots (FLIERS) observed in some PNe.

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The categories of this paper are: funct-an
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The categories of this paper are: comp-gas
19
The categories of this paper are: eess
16
The categories of this paper are: stat
0
The categories of this paper are: hep-ph
28
The categories of this paper are: alg-geom
10
The categories of this paper are: q-bio
1
The categories of this paper are: cs
25
The categories of this paper are: patt-sol
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The categories of this paper are: adap-org
13
The categories of this paper are: quant-ph
2
The categories of this paper are: math
30
The categories of this paper are: q-alg
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The categories of this paper are: hep-lat
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The categories of this paper are: atom-ph
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The categories of this paper are: supr-con