Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Multi-transition VLBA observations of circumstellar SiO masers   On this paper, we present simultaneous VLBA observations of the J=1-0 and
J=2-1 rotational lines in the v=1 and v=2 vibrationally excited states of SiO
(at 7 and 3 mm wavelengths). We have mapped these four maser lines in the
circumstellar envelopes of three AGB stars: IRC +10011, Chi Cyg and TX Cam. We
study the relative spatial distribution between these maser lines. In
particular, for the two v=1 transitions, we found that the J=1-0 and J=2-1
maser spot distributions are unalike, challenging all the current theoretical
pumping mechanisms for SiO masers (which predict quite similar distribution for
maser lines in the same vibrational excited state).

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The categories of this paper are: stat
23
The categories of this paper are: solv-int
1
The categories of this paper are: cs
36
The categories of this paper are: cmp-lg
2
The categories of this paper are: math
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The categories of this paper are: math-ph
26
The categories of this paper are: bayes-an
31
The categories of this paper are: ao-sci
32
The categories of this paper are: atom-ph
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The categories of this paper are: q-fin
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The categories of this paper are: cond-mat
5
The categories of this paper are: gr-qc
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The categories of this paper are: eess
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The categories of this paper are: chao-dyn
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The categories of this paper are: nucl-th
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The categories of this paper are: patt-sol