RA1. RIB Development
(D. W. Stracener)
Experiments with high-intensity production beams from the ORIC will begin soon at the recently commissioned High Power Target Laboratory (HPTL). The first set of tests will be focused on the production of 25Al and 26Al beams from reactions on silicon. The targets that we plan to test include SiC fibers and pressed pellets of metal silicide powders, such as tungsten silicide and niobium silicide. Other target tests that will be made in the next few months include, thin liquid Ge for production of Se beams, different geometries for the fluorine production target, and high intensity tests on uranium carbide targets with densities that are significantly higher than those presently used.
In the last newsletter we reported on the first experiments with a laser ion source using Ti:sapphire lasers. Another series of tests were recently completed where beams of Cu, Sn, and Ni were produced. This was the first demonstration of three-photon resonant ionization of Cu in a hot-cavity laser ion source using Ti:Sapphire lasers. The ionization efficiency for Cu was 2.4% and, for the first time, frequency quadrupling of the Ti:Sapphire laser was successfully utilized. In addition, we measured the emittance of laser-generated and surface-ionized ion beams, and made measurements of the temporal structures of laser ions with respect to the laser pulse at different source temperatures. The temporal structures of laser ions generated from hot cavities of three different lengths were also measured. These measurements were made in collaboration with Klaus Wendt and his group from Mainz who brought the Ti:sapphire lasers and successfully operated them. A 100 W, 10 kHz Nd:YAG pump laser has been purchased by the ORNL Physics Division and a order for a Ti:sapphire lasers has been placed.
On-line measurements at the On-Line Test Facility (OLTF) during the last few months have included, alpha-particle beams on a liquid Ge target for the production of neutron deficient Se beams, proton-induced fission in a thorium oxide target, release of Re beams from a tungsten oxide target, and measurements of yields of fission fragments from three different UC targets that varied in density and porosity. Analysis of these data sets is continuing and the results will be reported later.