Article ID Journal Published Year Pages File Type
1682955 Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 2011 5 Pages PDF
Abstract
In this work, we present the experimental results of a laser ion source (LIS) implemented for ion accelerators. A KrF excimer laser beam operating at 248 nm was focused on a solid target mounted inside a vacuum chamber in order to obtain the plasma. The laser energy was fixed at 11.5 mJ/pulse. The ion components of the plasma were extracted and accelerated up to 160 keV per charge state by a double gap system formed in two different stages. The beam cross section was circular, 1.5 cm in diameter. Using Cu and Y disks, as laser targets, we produced ion beams containing 1.2 × 1011 ions/pulse (0.7 × 1011 ions/cm2). Applying a total accelerating voltage of 60 kV we obtained an increase in ion dose up to 3.4 × 1011 ions/pulse, (2 × 1011 ions/cm2) for the Cu target and up to 6.3 × 1011 ions/pulse (3.5 × 1011 ions/cm2) for the Y target. The characterization of the plasma was performed using a Faraday cup for the electromagnetic properties, and a pepper pot system for the geometric ones. At 60 kV accelerating voltage and 5.5 mA output current the normalized beam emittance resulted in 0.22 π mm mrad for the Cu target, while under the same accelerating voltage, but with 7.4 mA output current, the normalized beam emittance resulted in 0.14 π mm mrad for the Y target.
Related Topics
Physical Sciences and Engineering Materials Science Surfaces, Coatings and Films
Authors
, ,