Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Selective highly charged ions as the prospective optical clock
  candidates with quality factors larger than $10^{15}$   We propose here a few selective highly charged ions (HCIs), namely Ni$^{12+}$
and Cu$^{13+}$, Pd$^{12+}$ and Ag$^{13+}$, that not only promise to be very
high accurate optical clocks below $10^{-19}$ uncertainties, but also offer
quality factors larger than $10^{15}$ and yet possess simple atomic structures
for the experimental set-up. Moreover, these ions have strong optical
magnetic-dipole (M1) transitions than the previously proposed HCI clocks. They
can be used for the cooling and detection techniques. To demonstrate the
projected fractional uncertainties below $10^{-19}$ level, we have estimated
the typical orders of magnitudes due to many of the conventional systematics
manifested in an atomic clock experiment, such as Zeeman, Stark, black-body
radiation, and electric quadrupole shifts, by performing calculations of the
relevant atomic properties.

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The categories of this paper are: hep-lat
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The categories of this paper are: cmp-lg
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The categories of this paper are: ao-sci
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The categories of this paper are: math-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: chem-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: dg-ga
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The categories of this paper are: adap-org
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The categories of this paper are: gr-qc
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The categories of this paper are: q-fin
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The categories of this paper are: quant-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: funct-an
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The categories of this paper are: astro-ph
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The categories of this paper are: hep-ph