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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, “M. S. Safronova, V. A. Dzuba, V. V. Flambaum, U. I. Safronova, S. G. Porsev, and M. G. Kozlov, Phys. Rev. A 90, 042513 (2014), DOI: https://doi.org/10.1103/PhysRevA.90.042513", unless noted otherwise.
    Notes:
    1) Ground state ionization energy \(\ \rm{E}_{\rm{IP}} \)=243.1 eV is given in, “M. S. Safronova, V. A. Dzuba, V. V. Flambaum, U. I. Safronova, S. G. Porsev, and M. G. Kozlov, Phys. Rev. Lett. 113, 030801 (2014), DOI: https://doi.org/10.1103/PhysRevLett.113.030801".
    2) Experimental energies from are used in calculation of transition rate and lifetime.
    3) Transition types ‘M1’, M2’, ‘E1’, ’E2’ and ‘E3’ stand for magnetic dipole, magnetic quadrupole, electric dipole, electric quadrupole and electric octupole transition, respectively.
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    J. Sugar and V. Kaufman, Phys. Scr. 24, 742 (1981),
    DOI: https://doi.org/10.1088/0031-8949/24/4/010. Close

    State Energy
    		\(\ \lambda \) \( \alpha \)-variation sensitivity q Enhancement factor K Lifetime
    \(\ \) \(\ \rm{cm}^{-1} \) nm \(\ \rm{cm}^{-1} \) \(\ \) \(\ \)
    $$5s_{1/2}$$ 0 $$ $$ 0 $$ $$ $$ $$
    $$4f_{5/2}$$ 55870 179 104229 3.7 1.3 \(\ \times 10^{6} \)
    $$4f_{7/2}$$ 60300 165.8 108243 3.6 0.996
    $$5p_{1/2}$$ 185066 54.03 15953 0.2 0.204 \(\ \times 10^{-9} \)
    $$5p_{3/2}$$ 234864 42.58 72079 0.6 0.0984 \(\ \times 10^{-9} \)

    Transition Type Transition energy
    		\(\ \lambda \)
    		Matrix element
    		 Transition rate
    \(\ \) \(\ \) \(\ \rm{cm}^{-1} \) nm \(\ \) \(\ \rm{s}^{-1} \)
    $$4f_{5/2} -5s_{1/2}$$ E3 55870 179.1 0.922 a.u. 7.568 \(\ \times 10^{−7} \)
    $$4f_{5/2} -5s_{1/2}$$ M2 55870 179 0.00038 \(\ \mu_B \) 1.987 \(\ \times 10^{−11} \)
    $$4f_{7/2} -4f_{5/2}$$ M1 4430 2257 1.85 \(\ \mu_B \) 1.004
    $$4f_{7/2} -4f_{5/2}$$ E2 4430 2257 0.285 a.u. 1.936 \(\ \times 10^{−6}\)
    $$4f_{7/2} -5s_{1/2}$$ E3 60300 165.8 1.076 a.u. 1.319 \(\ \times 10^{−6} \)
    $$5p_{1/2} -5s_{1/2}$$ E1 185066 54.03 0.873 a.u. 4.899 \(\ \times 10^{9} \)
    $$5p_{3/2} -5s_{1/2}$$ E1 234864 42.58 1.245 a.u. 1.016 $$\times 10^{10}$$