Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Lamb Shift of 3P and 4P states and the determination of $\alpha$   The fine structure interval of P states in hydrogenlike systems can be
determined theoretically with high precision, because the energy levels of P
states are only slightly influenced by the structure of the nucleus. Therefore
a measurement of the fine structure may serve as an excellent test of QED in
bound systems or alternatively as a means of determining the fine structure
constant $\alpha$ with very high precision. In this paper an improved analytic
calculation of higher-order binding corrections to the one-loop self energy of
3P and 4P states in hydrogen-like systems with low nuclear charge number $Z$ is
presented. A comparison of the analytic results to the extrapolated numerical
data for high $Z$ ions serves as an independent test of the analytic
evaluation. New theoretical values for the Lamb shift of the P states and for
the fine structure splittings are given.

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The categories of this paper are: cond-mat
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The categories of this paper are: ao-sci
20
The categories of this paper are: acc-phys
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The categories of this paper are: astro-ph
18
The categories of this paper are: econ
7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
33
The categories of this paper are: plasm-ph
17
The categories of this paper are: q-fin
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The categories of this paper are: adap-org
30
The categories of this paper are: q-alg
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The categories of this paper are: hep-ex
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The categories of this paper are: nlin
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The categories of this paper are: comp-gas
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The categories of this paper are: hep-lat
36
The categories of this paper are: cmp-lg