Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Relativistic nuclear recoil corrections to the energy levels of
  hydrogen-like and high $Z$ lithium like atoms in all orders in $\alpha Z$   The relativistic nuclear recoil corrections to the energy levels of
low-laying states of hydrogen-like and high $Z$ lithium-like atoms in all
orders in $\alpha Z$ are calculated. The calculations are carried out using the
B-spline method for the Dirac equation.
  For low $Z$ the results of the calculation are in good agreement with the
$\alpha Z$ -expansion results. It is found that the nuclear recoil
contribution, additional to the Salpeter's one, to the Lamb shift ($n=2$) of
hydrogen is $-1.32(6)\,kHz$. The total nuclear recoil correction to the energy
of the $(1s)^{2}2p_{\frac{1}{2}}-(1s)^{2}2s$ transition in lithium-like uranium
constitutes $-0.07\,eV$ and is largely made up of QED contributions.

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The categories of this paper are: acc-phys
0
The categories of this paper are: hep-ph
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The categories of this paper are: math-ph
27
The categories of this paper are: comp-gas
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The categories of this paper are: hep-lat
19
The categories of this paper are: eess
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The categories of this paper are: cmp-lg
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The categories of this paper are: solv-int
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The categories of this paper are: dg-ga
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The categories of this paper are: funct-an
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The categories of this paper are: stat
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The categories of this paper are: chao-dyn
31
The categories of this paper are: ao-sci
7
The categories of this paper are: hep-th
34
The categories of this paper are: chem-ph
2
The categories of this paper are: math