Relative and absolute dipole oscillator strengths in the Rydberg series of Cd I

Abstract

Relative dipole oscillator strengths for the transitions 5s 2 1 S 0 → 5snp 1 P 1 (8 n 13) in cadmium have been measured using magneto-optical rotation spectroscopy in the VUV. The uncertainty in the relative oscillator strengths is estimated to be 3%. Absolute oscillator strengths were determined on the basis of the known oscillator strength of the 5s → 11p transition. Our experimental results agree with quantum defect orbital calculations which we have carried out for transitions in the principal series in cadmium up to 5s → 32p. A revised value of 4 ± 2 Mb for the total photoionization cross section at the ionization threshold is proposed.

Radiative lifetime and transition probabilities inCdIandCdII

“…Experimental transition probabilities in Cd I were obtained with an emission technique [21], eventually combined with the hook method [22]. Precise oscillator strength values of the 5s 2 1 S 0 -5snp 1 P o ͑n =8-13͒ transitions were measured by a magneto-optical rotation method [23] and the sumfrequency mixing in Cd vapor was considered for determination of matrix elements along the Cd I resonance series [24]. *Electronic address: kblagoev@issp.bas.bg Theoretical work in the same atom includes the use of different methods such as the scaled Thomas-Fermi-Dirac approach [25], the Coulomb approximation [26], the extended Bates-Damgaard (nodal boundary condition) method [27], a relativistic "quantum orbital" [28], or a HF method [29].…”

Dipole-dipole polarizability of the cadmium $\mathbf{^1S_0}$ state revisited

“…(df /dE) ion = 4.5198 × 10 −8 m is used 21 . The resulting values of the dipole sums S(0) and S(−2) are given in Table II.…”

“…21 13 7143140 0.0012 Ref. 21 these data directly. Instead of this we fix f 5 to the experimental value of f 5 = 1.3442 25 .…”

“…(df /dE) ion can be obtained from photoionization cross sections 21 . According to the Kuhn-Reiche-Thomas (KRT) sum rule for a N−electron system S(0) = N 14,22,23 .…”

“…Input data in the range between 10.2 ≤ E/eV ≤ 29779 eV are taken from Henke et al 28 , in the range 29779 < E/eV ≤ 433000 photoabsorption cross sections compiled by Chantler 29 are used. The photoionization cross section of σ = 4 ± 2 Mbarn at I p = 8.9938 eV is taken from Ahmad et al 21 .…”