The FERRUM project: Branching ratios and atomic transition probabilities of Fe II transitions from the 3d6(a 3F)4p subconfiguration in the visible to VUV spectral region

We report measurements of the relative intensities of 81 emission linesof Fe II between 160 nm and 350 nm (62 168 cm-1 to 28 564cm-1) from 4 levels by high resolution Fourier transformspectrometry, using a Penning discharge lamp as light source. Theserelative intensities have been used to determine the line branchingfractions, which have then been combined with accurate experimentalradiative lifetime measurements reported recently to give absolutetransition probabilities and oscillator strengths for 81 lines. Theaccuracy of these f-values is compared with other previous experimentalmeasurements, and with theoretical values. The new transitionprobabilities will allow accurate determinations of Fe II abundances ina wide variety of astrophysical objects. Tables 2 and 3 are onlyavailable in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/377/36