Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Decay of the low-energy nuclear $^{229m}$Th isomer via atomic Rydberg
  states   In the paper, a unique process of the decay of the $^{229m}$Th($3/2^+,8.28\pm
0.17$ eV) low energy nuclear isomer via the internal conversion (IC) channel on
Rydberg states is considered for the first time. The Rydberg atom
$^{229m}$Th$^{+}+e^-_{Ry}$ is a unique object where IC is possible exclusively
on the Rydberg electron $e^-_{Ry}$. It is shown that in the
$^{229m}$Th$^{4+}+e^-_{Ry}$ system a) IC on the electron states with relatively
small values of the principal quantum number $n$ and the orbital moment $l$ is
practically completely suppressed, b) IC probability, $W_{IC}$, on the
$\psi_{ns_{1/2}}({\bf{r}})$ states is proportional to $|\psi_{ns_{1/2}}(0)|^2$
and can be related with the energy of the hyperfine interaction of the Rydberg
electron with the nucleus, c) $W_{IC}$ decreases rapidly with the increase of
$n$ in the range from 10 to 50, and in the range $n\gtrsim 150$ $W_{IC}$
changes as ${\text{Const}}/n^3$ typical for hydrogen-like ions, d) at
$n\thickapprox 10$--30, $W_{IC}$ as a function of $l$ has a characteristic
"knee" between $l=3$ and $l=4$, i.e. a three order of magnitude decrease of
$W_{IC}$ due to the qualitative change in the ratio between the centrifugal and
shielding potentials.

20
The categories of this paper are: acc-phys
3
The categories of this paper are: physics
16
The categories of this paper are: stat
35
The categories of this paper are: mtrl-th
37
The categories of this paper are: supr-con
21
The categories of this paper are: adap-org
24
The categories of this paper are: dg-ga
11
The categories of this paper are: hep-lat
8
The categories of this paper are: hep-ex
33
The categories of this paper are: plasm-ph
14
The categories of this paper are: math-ph
26
The categories of this paper are: bayes-an
31
The categories of this paper are: ao-sci
9
The categories of this paper are: nlin
22
The categories of this paper are: chao-dyn
19
The categories of this paper are: eess