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    Energies are given in cm\(^{-1}\). See this link for conversion factors. Electric matrix elements are given in atomic units. Magnetic dipole matrix elements are given in Bohr magnetons, \(\mu_B\). The values of magnetic-dipole hyperfine constants A are listed in MHz. Dipole polarizabilities \(\alpha\) are given in atomic units, \(a_0^3\), where \(a_0\) is the Bohr radius. The atomic units for \(\alpha\) can be converted to SI units via \(\alpha /h \rm{[Hz/(V/m)^2]}\)\(=2.48832 \times 10^{-8} \alpha \) [a.u.], where the conversion coefficient is \( 4\pi \epsilon_0 a^3_0/h \) and the Planck constant \(h\) is factored out.

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    Data are taken from, “S. G. Porsev, U. I. Safronova, M. S. Safronova, P. O. Schmidt, A. I. Bondarev, M. G. Kozlov, I. I. Tupitsyn, and C. Cheung, Phys. Rev. A 102, 012802 (2020), DOI: https://doi.org/10.1103/PhysRevA.102.012802", unless noted otherwise.
    Notes:
    1) The uncertainty of the clock transition energy is \(\ \sim \) 600 cm\(\ ^{-1} \)
    2) Estimated accuracy of the hyperfine constant is 20-30%.
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    State Energy \(\ \lambda \) Lifetime \(\ \langle \gamma J ||Q|| \gamma J\rangle \) Quadrupole moment Polarizability \(\ A/g_{_{_{I}}} \)
    \(\ \) \(\ \rm{cm^{-1}} \) nm s \(\ |e|a_0^2 \) \(\ |e|a_0^2 \) \(\ a_0^3 \) MHz
    $$(6s^2\,\,5f)^o_{5/2}$$ 0 $$\approx 0.80$$ 0.39 0.961 1900
    $$(6s^2\,\,6p)^o_{1/2}$$ 20611 485.177818 6 $$ $$ 0 0.919 195000
    $$(6s^2\,\,5f)^o_{7/2}$$ 20895 478.583393 0.0095 $$ $$ $$ $$ $$ $$ $$ $$
    $$(6s^2\,\,6p)^o_{3/2}$$ 243081 41.138551 $$7 \times 10^{-6}$$ $$ $$ $$ $$ $$ $$ $$ $$
    $$(6s\,\,5f^2)_{7/2}$$ 200890 49.778486 $$ $$ $$ $$ $$ $$ $$ $$ $$ $$
    $$(6s\,\,5f^2)_{9/2}$$ 206765 48.364085 $$ $$ $$ $$ $$ $$ $$ $$ $$ $$
    $$(6s\,\,5f^2)_{3/2}$$ 208501 47.961401 $$ $$ $$ $$ $$ $$ $$ $$ $$ $$
    $$(6s\,\,5f^2)_{5/2}$$ 210182 47.577814 $$ $$ $$ $$ $$ $$ $$ $$ $$ $$
    $$(6s\,5f\,6p)_{5/2}$$ 217050 46.072334 $$ $$ $$ $$ $$ $$ $$ $$ $$ $$

    Clock transition \(\ 6s^2\,6p_{1/2} \rightarrow \, 6s^2\,5f_{5/2}\)
    Clock frequency 6.1 \(\ \times 10^{14}\) Hz
    Fractional Black Body Radiation shift at T=300K $$ 5.7 \times 10^{-19}$$