Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The 2S-2P Lamb Shift in He+   The current theoretical status of the Lamb shift in He+ is discussed. Recent
calculations of two-loop binding corrections to the Lamb shift significantly
shift the theoretical value of the "classic" Lamb shift in He+, i.e. of the
2S_1/2-2P_1/2-interval. In this brief research note, we present a new
(theoretical) value for this interval which reads 14041.474(42) Mhz. The
theoretical uncertainty is reduced as well as the discrepancy between theory
and experiment. Planned measurements should be of help in further elucidating
the situation.

15
The categories of this paper are: nucl-ex
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The categories of this paper are: solv-int
36
The categories of this paper are: cmp-lg
17
The categories of this paper are: q-fin
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The categories of this paper are: eess
10
The categories of this paper are: q-bio
35
The categories of this paper are: mtrl-th
5
The categories of this paper are: gr-qc
21
The categories of this paper are: adap-org
6
The categories of this paper are: astro-ph
32
The categories of this paper are: atom-ph
18
The categories of this paper are: econ
16
The categories of this paper are: stat
1
The categories of this paper are: cs
27
The categories of this paper are: comp-gas
30
The categories of this paper are: q-alg