Absolute photoionization cross-section measurements of the Kr I isoelectronic sequence

Abstract

Type of publicationArticle (peer-reviewed) Photoionization spectra have been recorded in the 4s, 4p, and 3d resonance regions for the Kr I isoelectronic sequence using both the dual laser produced plasma ͑DLP͒ technique ͑at DCU͒ to produce photoabsorption spectra, and the merged ion beam and synchrotron radiation technique ͑at ASTRID͒ to measure absolute photoionization cross sections. Profile parameters are compared for the 4s-np resonances of Rb + and Sr 2+ . Many 4p → ns, md transitions are identified with the aid of Hartree-Fock calculations, and consistent quantum defects are observed for the various ns and md Rydberg series. Absolute single and double photoionization cross sections recorded in the 3d region for Rb + and Sr 2+ ions show preferential decay via double photoionization. This is only the second report to our knowledge where both the DLP technique and the merged-beam technique have been used simultaneously to record photoionization spectra, and the advantages of both techniques ͑i.e., better resolution in the case of DLP and values for absolute photoionization cross sections in the case of the merged-beam technique͒ are highlighted.

Valence-shell single photoionization of Kr+ions: Experiment and theory

“…For some of these ions, photoionization (PI) parameters have been measured; Kr + [4], Kr 3+ [9], Kr 5+ [10], the Kr iso-electronic sequence [11], K-shell photoionization of Kr + [12] and extreme UV radiation photoionization [13,14].…”

Photoionization of Rb2+ions in the valence energy region 37–44 eV

“…With respect to Rb, specifically in support of astrophysical applications, recent work includes calculations of 538 transition energies, transition probabilities, and oscillator strengths of Rb 3+ , substantially adding to the known data [19,20], and calculations of transition probabilities and collision strengths for 10 forbidden transitions originating in the ground state of Rb 3+ [6]. In addition, photoionization cross sections of Rb + were measured [21][22][23] and calculated [24,25].…”

Screening Constant by Unit Nuclear Charge Photoionization of Rb\(^{2+}\) Ions

“…Photoionization studies of Rb ions (Sneden et al [3]; Kilbane et al [1]; Mueller et al [2])remain an active field of investigations due to their importance for modeling astrophysical objects such those in the asymptotic giant branch (AGB) region. It is widely believed that, a major source of discrepancy is the quality of the atomic data used in the modelling (Mishenina et al [4]; Roederer et al [5,6]; Frebel et al [7]).…”