Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Observations of Water Masers in the NGC 1333 IRAS 4 Region   The NGC 1333 IRAS 4 region was observed in the 22 GHz H2O maser line with an
angular resolution of about 0.08 arcseconds. Two groups of masers were
detected, one near IRAS 4A and the other near BI. Among the eight maser spots
detected near IRAS 4A, six spots are located close to A2, within 100 AU, and
the maser velocities are also near the systemic velocity of the cloud core.
These masers are probably related with the circumstellar disk. Since there is
no maser spot detected around A1, the star forming process is relatively more
active in A2 than in A1. Four maser spots were detected near IRAS 4BI. Since
most of them are distributed along a straight line in the direction of the
outflow, BI masers are most likely related with the jet or outflow. The
disk-outflow dichotomy of H2O masers is discussed briefly. No maser was
detected near H2O(C), another maser source reported previously.

19
The categories of this paper are: eess
13
The categories of this paper are: quant-ph
23
The categories of this paper are: solv-int
18
The categories of this paper are: econ
5
The categories of this paper are: gr-qc
10
The categories of this paper are: q-bio
11
The categories of this paper are: hep-lat
14
The categories of this paper are: math-ph
24
The categories of this paper are: dg-ga
32
The categories of this paper are: atom-ph
21
The categories of this paper are: adap-org
8
The categories of this paper are: hep-ex
25
The categories of this paper are: patt-sol
26
The categories of this paper are: bayes-an
15
The categories of this paper are: nucl-ex
34
The categories of this paper are: chem-ph