Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Electron attachment to valence-excited CO   The possibility of electron attachment to the valence $^{3}\Pi$ state of CO
is examined using an {\it ab initio} bound-state multireference configuration
interaction approach. The resulting resonance has $^{4}\Sigma^{-}$ symmetry;
the higher vibrational levels of this resonance state coincide with, or are
nearly coincident with, levels of the parent $a^{3}\Pi$ state. Collisional
relaxation to the lowest vibrational levels in hot plasma situations might
yield the possibility of a long-lived CO$^-$ state.

17
The categories of this paper are: q-fin
4
The categories of this paper are: cond-mat
25
The categories of this paper are: patt-sol
5
The categories of this paper are: gr-qc
23
The categories of this paper are: solv-int
8
The categories of this paper are: hep-ex
6
The categories of this paper are: astro-ph
16
The categories of this paper are: stat
15
The categories of this paper are: nucl-ex
30
The categories of this paper are: q-alg
31
The categories of this paper are: ao-sci
20
The categories of this paper are: acc-phys
32
The categories of this paper are: atom-ph
14
The categories of this paper are: math-ph
1
The categories of this paper are: cs
7
The categories of this paper are: hep-th