Investigation of pressure and varied electric field effect on low pressure ionization chamber resolution

Abstract

The ISAC charged particle reaction spectroscopy station (IRIS), is an experimental facility stationed at TRIUMF Vancouver. IRIS was developed to study direct reactions with rare isotope beams. It is a tremendous challenge to create particle beams in a range far from stability; in the production process beam contamination with the same mass number can comprise up to 90% of the produced beam. To identify all beam constituents, IRIS uses a low-pressure ionization chamber. The low pressure ionization chamber used is a new development, therefore detailed studies on effect of various parameters on the ionization chamber resolution were carried out using rare isotope beams of 11Li, and 20Mg, as well as stable ion beams of 10C, 12Be, and 86Kr.It was observed that IC resolution was directly dependent on how much energy was lost, as well as how large the energy straggling was for each experiment. When considering the more massive beam of 86Kr, changes in the FC/C ratio showed little to no effect on changes in the resolution.