Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Molecular Gas Dynamics in NGC 6946: a Bar-driven Nuclear Starburst
  "Caught in the Act"   We present high angular resolution ~1" and 0.6" mm-interferometric
observations of the 12CO(1-0) and 12CO(2-1) line emission in the central 300pc
of the late-type spiral galaxy NGC6946. The data, obtained with the IRAM
Plateau de Bure Interferometer (PdBI), allow the first detection of a molecular
gas spiral in the inner ~10" (270pc) with a large concentration of molecular
gas (M(H_2) ~1.6x10^7M_sun) within the inner 60pc. This nuclear clump shows
evidence for a ring-like geometry with a radius of ~10pc as inferred from the
p-v diagrams. Both the distribution of the molecular gas as well as its
kinematics can be well explained by the influence of an inner stellar bar of
about 400pc length. A qualitative model of the expected gas flow shows that
streaming motions along the leading sides of this bar are a plausible
explanation for the high nuclear gas density. Thus, NGC6946 is a prime example
of molecular gas kinematics being driven by a small-scale, secondary stellar
bar.

28
The categories of this paper are: alg-geom
32
The categories of this paper are: atom-ph
4
The categories of this paper are: cond-mat
9
The categories of this paper are: nlin
36
The categories of this paper are: cmp-lg
0
The categories of this paper are: hep-ph
10
The categories of this paper are: q-bio
23
The categories of this paper are: solv-int
26
The categories of this paper are: bayes-an
37
The categories of this paper are: supr-con
7
The categories of this paper are: hep-th
27
The categories of this paper are: comp-gas
24
The categories of this paper are: dg-ga
2
The categories of this paper are: math
34
The categories of this paper are: chem-ph
1
The categories of this paper are: cs