Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Transit flow models for low and high mass protostars   In this work, the gas infall and the formation of outflows around low and
high mass protostars are investigated. A radial self-similar approach to model
the transit of the molecular gas around the central object is employed. We
include gravitational and radiative fields to produce heated pressure-driven
outflows with magneto-centrifugal acceleration and collimation. Outflow
solutions with negligible or vanishing magnetic field are reported. They
indicate that thermodynamics is a sufficient engine to generate an outflow. The
magnetized solutions show dynamically significant differences in the axial
region, precisely where the radial velocity and collimation are the largest.
They compare quantitatively well with observations. The influence of the
opacity on the transit solutions is also studied. It is found that, when dust
is not the dominant coolant, such as in the primordial universe, mass infall
rates have substantial larger values in the equatorial region. This suggests
that star forming in a dust-free environment should be able to accrete much
more mass and become more massive than present day protostars.It is also
suggested that molecular outflows may be dominated by the global transit of
material around the protostar during the very early stages of star formation,
especially in the case of massive or dust-free star formation.

13
The categories of this paper are: quant-ph
15
The categories of this paper are: nucl-ex
12
The categories of this paper are: nucl-th
17
The categories of this paper are: q-fin
22
The categories of this paper are: chao-dyn
4
The categories of this paper are: cond-mat
34
The categories of this paper are: chem-ph
33
The categories of this paper are: plasm-ph
18
The categories of this paper are: econ
7
The categories of this paper are: hep-th
3
The categories of this paper are: physics
9
The categories of this paper are: nlin
1
The categories of this paper are: cs
27
The categories of this paper are: comp-gas
35
The categories of this paper are: mtrl-th
8
The categories of this paper are: hep-ex