Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spherical model of the Stark effect in external scalar and vector fields   The Bohr-Sommerfeld quantization rule and the Gamow formula for the width of
quasistationary level are generalized by taking into account the relativistic
effects, spin and Lorentz structure of interaction potentials. The relativistic
quasi-classical theory of ionization of the Coulomb system (V_{Coul}=-\xi/r) by
radial-constant long-range scalar (S_{l.r.}=(1-\lambda)(\sigma r+V_0)) and
vector (V_{l.r.}=\lambda(\sigma r+V_0)) fields is constructed. In the limiting
cases the approximated analytical expressions for the position E_r and width
\Gamma of below-barrier resonances are obtained. The strong dependence of the
width \Gamma of below-barrier resonances on both the bound level energy and the
mixing constant \lambda is detected. The simple analytical formulae for
asymptotic coefficients of the Dirac radial wave functions at zero and infinity
are also obtained.

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The categories of this paper are: cmp-lg
33
The categories of this paper are: plasm-ph
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The categories of this paper are: chem-ph
11
The categories of this paper are: hep-lat
24
The categories of this paper are: dg-ga
8
The categories of this paper are: hep-ex
27
The categories of this paper are: comp-gas
17
The categories of this paper are: q-fin
32
The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
4
The categories of this paper are: cond-mat
2
The categories of this paper are: math
31
The categories of this paper are: ao-sci
22
The categories of this paper are: chao-dyn
28
The categories of this paper are: alg-geom
21
The categories of this paper are: adap-org