Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Non-uniform convergence of two-photon decay rates for excited atomic
  states   Two-photon decay rates in simple atoms such as hydrogenlike systems represent
rather interesting fundamental problems in atomic physics. The sum of the
energies of the two emitted photons has to fulfill an energy conservation
condition, the decay takes place via intermediate virtual states, and the total
decay rate is obtained after an integration over the energy of one of the
emitted photons. Here, we investigate cases with a virtual state having an
energy intermediate between the initial and the final state of the decay
process, and we show that due to non-uniform convergence, only a careful
treatment of the singularities infinitesimally displaced from the photon
integration contour leads to consistent and convergent results.

29
The categories of this paper are: funct-an
10
The categories of this paper are: q-bio
31
The categories of this paper are: ao-sci
30
The categories of this paper are: q-alg
27
The categories of this paper are: comp-gas
11
The categories of this paper are: hep-lat
1
The categories of this paper are: cs
36
The categories of this paper are: cmp-lg
5
The categories of this paper are: gr-qc
28
The categories of this paper are: alg-geom
8
The categories of this paper are: hep-ex
34
The categories of this paper are: chem-ph
2
The categories of this paper are: math
15
The categories of this paper are: nucl-ex
14
The categories of this paper are: math-ph
19
The categories of this paper are: eess