Measurement of hyperfine structure constants, g values and tensor polarizability of excited states of Sm I

Abstract

Atomic-beam laser spectroscopy with fluorescence detection is applied to investigate the hyperfine structure (hfs), Stark and Zeeman effects of the electric dipole transitions of Sm i. The measurements are performed for the four transitions of 0 → 15650.55, 292.58 → 15650.55, 292.58 → 15567.32, and 1489.55 → 16890.59 cm −1 . The hfs constants of the upper and lower levels and the isotope shifts of the transitions are determined. The tensor polarizability of the 15650.55 cm −1 level is found to be α 2 = −556.2 ± 11.8 kHz/(kV/cm) 2 . Thanks to the accurate g values of the lower levels [Childs, W.J., Goodman, L.S.: Phys. Rev. A 6, 2011 (1972)], the g values of the upper levels are obtained from the observed Zeeman splittings. The values are found to be −0.115907(79), 2.22259(20) and 1.599968(51) for the 15650.55 cm −1 , 15567.32 cm −1 and 16890.59 −cm −1 levels, respectively.

Stark and Zeeman spectroscopies of 4f 66s6p 7G1-6 levels in Sm I under external electric and magnetic fields

“…They are the values measured by Kobayashi et al [9] and by Childs et al [16,18]. The IS's were found to have similar values.…”

“…(9). For the case of 4f 6 6s6p 7 G 1 level, the contributions of the opposite-parity levels except for the 4f 6 5d6s 7 G 1 level are negligibly small.…”

“…The leading configuration of the upper levels is 4f 6 6s6p. The 7 F 0,1 -7 G 1 transitions have been measured already by our group [9] and remeasured here only with electric field. There are also systematic studies of Stark spectroscopy in Sm I including the 4f 6 6s 2 7 F 1−6 and 4f 6 6s6p 7 G 1−3 levels [13,14].…”

“…It consists of a laser system, a vacuum chamber, a frequency calibration system and a data acquisition system. In the vacuum chamber, an atomic-beam oven and a fluorescence detecting system with external field devices are installed, and the details have been already reported in [9]. An Ar-ion laser (Coherent INNOVA-310) with 10-W power pumps a CW ring dye laser (Coherent CR899-29).…”

“…The laser spectroscopy of the 4f 6 6s6p 7 G 1 level has been performed to study several physical properties [9]; the study of isotope shift, hyperfine structure, Zeeman and Stark effects. As a result, it has been found that 4f 6 6s6p 7 G 1 level in Sm I has large tensor polarizability due to the mixing of the close-lying opposite-parity level under the electric field.…”