Valence-shell photoionization of the chlorinelike Ca3+ ion

Authors

Ghassan A. Alna’washi, The Hashemite UniversityFollow
M. Lu, University of Nevada - RenoFollow
M. Habibi, University of Nevada - Reno
R. A. Phaneuf, University of Nevada - RenoFollow
A. L. D. Kilcoyne, Lawrence Berkeley National LaboratoryFollow
A. S. Schlachter, Lawrence Berkeley National LaboratoryFollow
C. Cisneros, Universidad Nacional Autonoma de MexicoFollow
B. M. McLaughlin, Queen’s University BelfastFollow

Date of this Version

2010

Citation

Physical Review A 81, 053416 (2010); DOI: 10.1103/PhysRevA.81.053416

Abstract

Absolute photoionization measurements were performed for a mixture of ²P^o_3/2 ground-state and ²P^o_1/2 metastable-state Ca³⁺ ions over the photon energy range 65.7–104.6 eV by merging an ion beam with a beam of monochromatized synchrotron radiation. The ionization threshold energy of the ²P^o_3/2 ground state was measured to be 67.063 ± 0.015 eV, which is 0.207 eV lower than the value tabulated in the NIST database. Most of the observed resonances associated with multiple Rydberg series of autoionizing states have been assigned spectroscopically using the quantum defect form of the Rydberg formula, guided by relativistic Hartree-Fock calculations of resonance energies and oscillator strengths. Intermediate coupling R-matrix calculations performed using the semi-relativistic Breit-Pauli approximation are in suitable agreement with measured absolute photoionization cross section in the energy range studied for this complex Cl-like ion species.