A high-power laser ablation ion source for Penning trap studies of nuclear reaction products

A state of the art Penning trap is being developed at the National Superconducting Cyclotron Laboratory (NSCL) at Michigan State University to make precision mass measurements of rare isotopes. The system relies on thermalizing nuclear reaction products in a helium-filled cell and then extracting them from the gas through ion-manipulation and differential pumping. Atomic ions and clusters are needed to calibrate various aspects of the entire system such as transport efficiency and the main magnetic field. High-power laser ablation has proven to be a successful method for producing a wide range of ions under various conditions, including atmospheric pressure. We have developed a laser ablation system to explore the production of test beams using a variety of targets. Laser ablation studies of C, Al, Au, Ag, Cu, Fe, and Zn were carried out in a test chamber with the second harmonic, 532 nm, from a Q-switched Nd:YAG laser. Many studies were carried out under vacuum using an ion-drift system and mass analysis in a quadrupole mass filter. The ablation target and laser optics were moved to the gas cell used to collect the nuclear reaction products and several ablation studies were performed. An overview of the laser-ablation system as well as some of the results of this work will be presented