Isotope shift calculations for open-shell atoms and ions: an extension to the RATIP program

Abstract

During the past decade, the Ratip program has been found useful for calculating a variety of atomic properties, including energies, transition probabilities, Auger parameters as well as a number of excitation, ionization and capture cross sections for processes with a single electron in the continuum. Recently, in addition, this suite of programs was extended to predict also the isotope shift and hyperfine parameters of open-shell atoms and ions. Here, we review the latest developments of the Ratip program with emphasis on the specific mass-shift M sms and field-shift F parameters. Detailed computations for these parameters have been carried out especially for the 4s 2 S 1/2 − 4 p 2 P 1/2,3/2 transitions at ∼ 397 nm of singly-charged Ca + ions and are compared with available data from the literature.

Progress in laser spectroscopy at radioactive ion beam facilities

“…Alternatively, non-optical δ r 2 data [72] may be used, with the advantage that not only are the atomic factors F and M calibrated but also K(Z). Recent theoretical approaches are outlined in [73,74]. Absolute mean-square charge radii can be found by adding the optically measured δ r 2 to values of r 2 (generally for stable isotopes) where available from other methods, but with systematic errors dominated by the latter.…”

Atomic physics techniques for studying nuclear ground state properties, fundamental interactions and symmetries: status and perspectives

“…If we concentrate here on extracting nuclear ground state properties from measured HFS splittings and isotope shifts, today two major frontiers are visible: the treatment of complex atoms with many electrons [10] and simple atomic systems with one or very few electrons. The latter can be either very light atoms or ions, as discussed by Krzysztof Pachucki [11], having few electrons (for example, neutral lithium or ionic beryllium [12,13] or heavy ions that are hydrogen-or helium-like (for example, U 91+ or U 90+ [14][15][16]).…”

“…In medium-heavy and heavy multi-electron elements, slow but steady progress has been made over the last decades as discussed by Stefan Fritzsche [10]. Generally, the experimental accuracy is much higher than that of the hyperfine fields, which must be calculated in order to extract the information on nuclear ground state properties.…”