Study of even-parity highly excited states of Eu I with a three-colour stepwise resonant excitation

Abstract

Even-parity highly excited states of an europium (Eu) atom have been investigated by employing the three-colour stepwise resonant excitation technique. Seventy-eight even-parity states of the Eu atom have been detected in the energy region between 43 500 and 45 200 cm −1 with two different excitation schemes. With a detailed analysis of the experimental data, this work not only confirms or improves the previous results by determining their level energy, J assignment, but also reports 21 new states of the Eu atom with a unique J assignment. In addition, the information about relative line intensities of these 78 related transitions are also provided for the first time.

Field ionization process of Eu 4f76snp Rydberg states

“…Different J values converging to the same n of the Rydberg states can be distinguished in the lower energy levels of Fig. 3(a), [26] so we can see one n member corresponding to multiple EFI threshold F 0 in Table 1, however, the J value of higher n-value cannot be distinguished because of the line width of lasers, so higher n-value of the Rydberg states, one-to-one correspondence in Table 1.…”

Atomic Data: Division Xii / Commission 14 / Working Group Atomic Data

“…Additional publications of wavelengths, energy levels and line classifications include: Al IV-XI [96], Ar II [200], Ba I [298], Ca I [15,60] IS [229], Ca XI [119], Ce II [162], Cl I [44], Co II HFS [38], Cr I IS [262], Cr III [243], D I [213], Dy I HFS, IS [166], Er I [125], HFS, IS [123], Er II [272], Eu I [274], Fe I HFS, IS [148], Fe II [50,51,52,126], Fe VI-XIV [170], Fe VII-IX [284], Fe VII [286], Fe VIII [287,159], Fe IX-XVI [173], Fe IX [282,158], Fe X [134], Fe XI [291,288,135], Fe XII-XXII [278], Fe XIII [260], Fe XVII [289,94], Gd I IS [19,125], Ge I-II [200], H I IS [213,21], Hg I IS [231], Ho II HFS [102], K I IS, HFS [151,…”

Branching ratio and angular distribution of ejected electrons from Eu 4f 7 6p 1/2 n d auto-ionizing states

“…For the last decade, spectra of highly excited states of rare-earth atoms [1][2][3] have attracted considerable attention. Although the position and width, as well as the line shape of an auto-ionizing resonance on both Eu and Sm atoms, have been reported, [4][5][6] they are only relevant to total cross section of auto-ionization, yielding no information on the dynamical process of auto-ionization, such as the final states of ions, and phases of the wave function of the ejected electrons.…”