Licentiate Thesis: Lifetime measurements of metastable states in ions at an ion storage ring

by Erik Bäckström (Stockholm University, Department of Physics)

Wednesday 21 Dec 2011, 13:00 → 15:00 Europe/Stockholm

FA31

This licentiate thesis includes lifetime measurements of metastable states in the singly charged ions Cr+ and Fe+, respectively. The thesis reports the lifetimes of the 3d6(3G)4s a4G11/2 and 3d6(3D)4s b4D1/2 levels in Fe+ together with the lifetimes of the 3d4(a3D) c4D5/2 and 3d4(a3D)4s c4D7/2 levels in Cr+. The measurements have been performed at the ion storage ring CRYRING at the Manne Siegbahn Laboratory in Stockholm, Sweden. A laser probing technique has been developed and used for these measurements and is thoroughly explained in this thesis. In collaboration with astronomers in Lund, transition rates (A-values) of the forbidden transitions a4F7/2,9/2 - a4G11/2 in Fe+ has also been obtained and is reported. The results are also compared with existing theoretical calculations.