Journal article

Publication year: 2017

Journal: Journal of Physics B: Atomic, Molecular and Optical Physics

Volume number: 50

Issue number: 20

ISSN: 0953-4075

eISSN: 1361-6455

DOI Link: https://doi.org/10.1088/1361-6455/aa8ba8

Publisher: IOP Publishing

Abstract: 
Relative cross sections for the valence shell photoionisation (PI) of S-2 ground level and 2D metastable Ca+ ions were measured with high energy resolution by using the ion-photon merged-beams technique at the Advanced Light Source. Overview measurements were performed with a full width at half maximum bandpass of Delta E = 17 meV, covering the energy range 20-56. eV. Details of the PI spectrum were investigated at energy resolutions reaching the level of Delta E = 3.3 meV. The photon energy scale was calibrated with an uncertainty of +/- 5. meV. By comparison with previous absolute measurements the present experimental high-resolution data were normalized to an absolute cross-section scale and the fraction of metastable Ca+ ions that were present in the parent ion beam was determined to be 18% +/- 4%. Large-scale R-matrix calculations using the Dirac Coulomb approximation and employing 594 levels in the closecoupling expansion were performed for the Ca+(3s(2)3p(6)4s S-2(1/2)) and Ca+(3s(2)3p(6)3d D-2(3/2,5/2))levels. The experimental data are compared with the results of these calculations and previous theoretical and experimental studies.

Harvard Citation style: Mueller, A., Schippers, S., Phaneuf, R., Covington, A., Aguilar, A., Hinojosa, G., et al. (2017) Photoionisation of Ca⁺ ions in the valence-energy region 20-56eV: experiment and theory, Journal of Physics B: Atomic, Molecular and Optical Physics, 50(20), Article 205001. https://doi.org/10.1088/1361-6455/aa8ba8

APA Citation style: Mueller, A., Schippers, S., Phaneuf, R., Covington, A., Aguilar, A., Hinojosa, G., Bozek, J., Sant'Anna, M., Schlachter, A., Cisneros, C., & McLaughlin, B. (2017). Photoionisation of Ca⁺ ions in the valence-energy region 20-56eV: experiment and theory. Journal of Physics B: Atomic, Molecular and Optical Physics. 50(20), Article 205001. https://doi.org/10.1088/1361-6455/aa8ba8