Analysis of the even-parity Rydberg series of Gd I to determine its ionization potential and isotope shift

Abstract

Three-step resonance ionization mass spectroscopy has been performed to observe the even-parity Rydberg series converging to four states of Gd + (4f 7 5d6s( 10 D o 5/2 ), 4f 7 5d6s( 10 D o 7/2 ), 4f 7 5d6s( 10 D o 9/2 ) and 4f 7 5d6s( 8 S o 7/2 )). Using low-angular-momentum states as the second-step intermediate levels, simple and unperturbed series structures have been obtained. From an analysis of these structures, the first ionization potential of atomic Gd has been determined with improved accuracy as 49 601.45 ± 0.35 cm −1 . In addition, on the basis of the isotope shifts of the Rydberg states the isotope shift ( 160 Gd-154 Gd) of the ionization potential of −77 ± 20 mK has been found.

Measurement of holmium Rydberg series through magneto-optical trap depletion spectroscopy

“…Studies of the Rydberg spectra of neutral rare earth elements have been limited to date, with initial measurements of the ionization potentials for the full range of lanthanides [11] and actinides [12] and energy resolved Rydberg states for La [13], Eu [14], Dy [15], Lu [16], Gd [17], Sm [18], Th [19], Ce [20], Yb [21], Ac [22], Pu [23] and U [24]. In this paper we present the first high resolution spectroscopy of the 4f 11 6sns and 4f 11 6snd odd-parity Rydberg states of Ho in the range n = 40 − 101 using depletion measurements * hostetter@wisc.edu † msaffman@wisc.edu on a magneto optical trap (MOT).…”

Ablation plume structure and dynamics in ambient gas observed by laser-induced fluorescence imaging spectroscopy

“…Figure 3 shows the calculated absorption spectra for the Gd I 313.692-nm line together with the measured spectral profile of the dye laser. These absorption spectra were calculated from the natural isotope abundance and the reported isotope-shift data [38] considering the relative isotope shift factors [39,40]. Generally the absorption spectrum for ablated species becomes narrower at larger delay time from ablation owing to the reduction of Stark and Doppler broadenings.…”

Polarization-dependent laser resonance ionization of beryllium

“…This is particularity significant for the alkaline and alkaline-like element transitions 1 S 0 → 1 P • 1 → 1 S 0 . Due to the polarization relaxation by collisions with environmental atoms, the reported studies of this effect were typically performed on low-density media such as atomic beams [1][2][3][4][5][6][7][8][9], instead of a confined and hot environment like a hot-cavity laser ion source. Initially motivated by the observation of polarization dependence of beryllium (Be) ion yields during online radioactive beam delivery at TRIUMF's isotope separator and accelerator facility (ISAC), a systematic investigation of this effect was performed at the off-line laser ion source test stand (LIS-STAND) [10,11] with atoms in a hot-cavity environment.…”

“…Polarization-based isotopeselective photoionization of palladium and samarium isotopes were preformed [3,4]. This spectroscopic technique was also used to determine the J values in atomic structure studies [5][6][7][8]. All these reported studies were preformed with stable isotope samples and at low atom density -atomic beams.…”