Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Outflow activities in the young high-mass stellar object G23.44-0.18   We present an observational study towards the young high-mass star forming
region G23.44-0.18 using the Submillimeter Array. Two massive, radio-quiet
dusty cores MM1 and MM2 are observed in 1.3 mm continuum emission and dense
molecular gas tracers including thermal CH$_3$OH, CH$_3$CN, HNCO, SO, and OCS
lines. The $^{12}$CO (2--1) line reveals a strong bipolar outflow originated
from MM2. The outflow consists of a low-velocity component with wide-angle
quasi-parabolic shape and a more compact and collimated high-velocity
component. The overall geometry resembles the outflow system observed in the
low-mass protostar which has a jet-driven fast flow and entrained gas shell.
The outflow has a dynamical age of $6\times10^3$ years and a mass ejection rate
$\sim10^{-3} M_{\odot}$ year$^{-1}$. A prominent shock emission in the outflow
is observed in SO and OCS, and also detected in CH$_3$OH and HNCO. We
investigated the chemistry of MM1, MM2 and the shocked region. The dense core
MM2 have molecular abundances of 3 to 4 times higher than those in MM1. The
abundance excess, we suggest, can be a net effect of the stellar evolution and
embedded shocks in MM2 that calls for further inspection.

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The categories of this paper are: math-ph
12
The categories of this paper are: nucl-th
33
The categories of this paper are: plasm-ph
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The categories of this paper are: dg-ga
18
The categories of this paper are: econ
35
The categories of this paper are: mtrl-th
31
The categories of this paper are: ao-sci
36
The categories of this paper are: cmp-lg
11
The categories of this paper are: hep-lat
3
The categories of this paper are: physics
29
The categories of this paper are: funct-an
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The categories of this paper are: chao-dyn
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The categories of this paper are: adap-org
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The categories of this paper are: nlin
0
The categories of this paper are: hep-ph
8
The categories of this paper are: hep-ex