Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Galactic Center stellar cluster: The central arcsecond   With 10 years of high-resolution imaging data now available on the stellar
cluster in the Galactic Center, we analyze the dynamics of the stars at
projected distances $\leq1.2''$ from the central black hole candidate
Sagittarius A* (Sgr A*). We find evidence for radial anisotropy of the cluster
of stars surrounding Sgr A*. We confirm/find accelerated motion for 6 stars,
with 4 stars having passed the pericenter of their orbits during the observed
time span. We calculated/constrained the orbital parameters of these stars. All
orbits have moderate to high eccentricities. The center of acceleration
coincides with the radio position of Sgr A*. From the orbit of the star S2, the
currently most tightly constrained one, we determine the mass of Sgr A* to
$3.3\pm0.7\times10^{6}$M$_{\odot}$ and its position to $2.0\pm2.4$ mas East and
$2.7\pm4.5$ mas South of the nominal radio position. The data provide
compelling evidence that Sgr A* is a single supermassive black hole.

26
The categories of this paper are: bayes-an
14
The categories of this paper are: math-ph
11
The categories of this paper are: hep-lat
1
The categories of this paper are: cs
5
The categories of this paper are: gr-qc
33
The categories of this paper are: plasm-ph
10
The categories of this paper are: q-bio
15
The categories of this paper are: nucl-ex
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
34
The categories of this paper are: chem-ph
36
The categories of this paper are: cmp-lg
37
The categories of this paper are: supr-con
9
The categories of this paper are: nlin
27
The categories of this paper are: comp-gas
0
The categories of this paper are: hep-ph