Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Light-Assisted Cold Chemical Reactions of Barium Ions with Rubidium
  Atoms   Light-assisted reactive collisions between laser-cooled Ba+ ions and Rb atoms
were studied in an ion-atom hybrid trap. The reaction rate was found to
strongly depend on the electronic state of the reaction partners with the
largest rate constant (7(2) x 10^-11 cm^3 s^-1) obtained for the excited
Ba+(6s)+Rb(5p) reaction channel. Similar to the previously studied Ca+ + Rb
system, charge transfer and radiative association were found to be the dominant
reactive processes. The generation of molecular ions by radiative association
could directly be observed by their sympathetic cooling into a Coulomb crystal.
Potential energy curves up to the Ba+(6s)+Rb(5p) asymptote and
reactive-scattering cross sections for the radiative processes were calculated.
The theoretical rate constant obtained for the lowest reaction channel
Ba+(6s)+Rb(5s) is compatible with the experimental estimates obtained thus far.

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The categories of this paper are: cond-mat
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The categories of this paper are: supr-con
14
The categories of this paper are: math-ph
27
The categories of this paper are: comp-gas
30
The categories of this paper are: q-alg
28
The categories of this paper are: alg-geom
29
The categories of this paper are: funct-an
7
The categories of this paper are: hep-th
12
The categories of this paper are: nucl-th
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The categories of this paper are: astro-ph
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The categories of this paper are: hep-ph
2
The categories of this paper are: math
17
The categories of this paper are: q-fin
32
The categories of this paper are: atom-ph
22
The categories of this paper are: chao-dyn
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The categories of this paper are: nlin