Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Angular bremsstrahlung during $\alpha$-decay, emission from the internal
  region and unified formula of the bremsstrahlung probability   Model of angular bremsstrahlung of photons emitted during $\alpha$-decay is
presented. A special emphasis is given on development of unified formalism of
matrix elements in the dipole and multipolar approaches. A probability of the
emission of photons calculated on the basis of the multipole model without any
normalization on experimental data (i. e. in absolute scale) is found at
$90^{\circ}$ of the angle $\vartheta_{\alpha\gamma}$ between directions of
motion of the $\alpha$-particle (with its tunneling under barrier) and emission
of photons to be in a good agreement with the newest experimental data for the
$^{210}{\rm Po}$, $^{214}{\rm Po}$, and $^{226}{\rm Ra}$ nuclei. The spectrum
for $^{244}{\rm Cm}$ is found at $\vartheta_{\alpha\gamma} = 25^{\circ}$ to be
in satisfactory agreement with high limit of errors of experimental data of
Japanese group. A comparative analysis for the spectra calculated for
$^{210}{\rm Po}$ by the multipole and dipole approaches in the absolute scale
and with normalization on experimental data is performed. The emission of
photons from the internal well in the dipole approach is found to be not small
while the multipolar approach does not show such a strong dependence.
Distribution of the bremsstrahlung probability on the numbers of protons and
nucleons of the $\alpha$-decaying nucleus in selected region close to
$^{210}{\rm Po}$ is obtained. An unified formula of the bremsstrahlung
probability during the $\alpha$-decay of arbitrary nucleus expressed directly
through the $Q_{\alpha}$-value and numbers $A_{p}$, $Z_{p}$ of nucleons and
protons of this nucleus is proposed.

19
The categories of this paper are: eess
3
The categories of this paper are: physics
20
The categories of this paper are: acc-phys
30
The categories of this paper are: q-alg
18
The categories of this paper are: econ
17
The categories of this paper are: q-fin
9
The categories of this paper are: nlin
33
The categories of this paper are: plasm-ph
25
The categories of this paper are: patt-sol
22
The categories of this paper are: chao-dyn
37
The categories of this paper are: supr-con
23
The categories of this paper are: solv-int
11
The categories of this paper are: hep-lat
26
The categories of this paper are: bayes-an
24
The categories of this paper are: dg-ga
10
The categories of this paper are: q-bio