Fe II lifetimes and transition probabilities

Institut für Atom- und Molekülphysik, Abteilung Plasmaphysik, Universität Hannover, Callinstrasse 38, 30167 Hannover, Germany e-mail: roman.schnabel@aei.mpg.de

Corresponding author: R. Schnabel, roman.schnabel@aei.mpg.de

Received: 1 September 2003
Accepted: 30 October 2003

Abstract

Fe II radiative lifetimes were measured applying the time-resolved nonlinear laser-induced fluoresence technique. We investigated 21 levels of up to 47 000 cm^-1. The uncertainties are typically 2-3%. The lifetimes provide an improved absolute scale to our branching fractions which were measured with a Fourier transform spectrometer and a high–resolution grating spectrometer and which have been published earlier. We report absolute transition probabilities of 140 Fe II lines in the wavelength range 220–780 nm. The overall uncertainties are estimated to be 6% for the strong and up to 26% for the weak transitions. The results are compared with recent experimental data from the literature. Our large set of accurate data can be used for a reliability check of theoretical data calculated for iron abundances in astrophysical plasmas.