Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Infrared and visible laser spectroscopy for highly-charged Ni-like ions   Application of visible or infrared (IR) lasers for spectroscopy of
highly-charged ions (HCI) has not been particularly extensive so far due to a
mismatch in typical energies. We show here that the energy difference between
the two lowest levels within the first excited configuration $3d^94s$ in
Ni-like ions of heavy elements from $Z_N$=60 to $Z_N$=92 is within the range of
visible or near-IR lasers. The wavelengths of these transitions are calculated
within the relativistic model potential formalism and compared with other
theoretical and limited experimental data. Detailed collisional-radiative
simulations of non-Maxwellian and thermal plasmas are performed showing that
photopumping between these levels using relatively moderate lasers is
sufficient to provide a two-order of magnitude increase of the pumped level
population. This accordingly results in a similar rise of the x-ray line
intensity thereby allowing control of x-ray emission with visible/IR lasers.

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The categories of this paper are: dg-ga
14
The categories of this paper are: math-ph
12
The categories of this paper are: nucl-th
21
The categories of this paper are: adap-org
35
The categories of this paper are: mtrl-th
34
The categories of this paper are: chem-ph
37
The categories of this paper are: supr-con
27
The categories of this paper are: comp-gas
22
The categories of this paper are: chao-dyn
8
The categories of this paper are: hep-ex
4
The categories of this paper are: cond-mat
31
The categories of this paper are: ao-sci
30
The categories of this paper are: q-alg
16
The categories of this paper are: stat
18
The categories of this paper are: econ
25
The categories of this paper are: patt-sol