Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Surface location of sodium atoms attached to $^3$He nanodroplets   We have experimentally studied the electronic $3p\leftarrow 3s$ excitation of
Na atoms attached to $^3$He droplets by means of laser-induced fluorescence as
well as beam depletion spectroscopy. From the similarities of the spectra
(width/shift of absorption lines) with these of Na on $^4$He droplets, we
conclude that sodium atoms reside in a ``dimple'' on the droplet surface and
that superfluid-related effects are negligible. The experimental results are
supported by Density Functional calculations at zero temperature, which confirm
the surface location of sodium on $^3$He droplets, and provide a detailed
description of the ``dimple'' structure. The calculated shift of the excitation
spectra for the two isotopes is in good agreement with the experimental data.

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The categories of this paper are: astro-ph
30
The categories of this paper are: q-alg
15
The categories of this paper are: nucl-ex
0
The categories of this paper are: hep-ph
29
The categories of this paper are: funct-an
36
The categories of this paper are: cmp-lg
18
The categories of this paper are: econ
35
The categories of this paper are: mtrl-th
20
The categories of this paper are: acc-phys
31
The categories of this paper are: ao-sci
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The categories of this paper are: math-ph
33
The categories of this paper are: plasm-ph
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The categories of this paper are: q-bio
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The categories of this paper are: hep-lat
12
The categories of this paper are: nucl-th
28
The categories of this paper are: alg-geom