Design and Performance of a Heavy Ion Detector Using a Gridded Ionization Chamber with Helical Position-Sensitive Proportional Counter

摘要

A counter specifically designed for heavy ions and low-energy helium ions has been constructed for use in the focal plane of a Q3D spectrometer. The counter utilizes a gridded ionization chamber to measure energy loss and total energy of the particles incident on the detector and a helical proportional chamber to establish the position and hence the momentum along the focal plane. The ionization chamber information is used to establish the mass and charge of the incident particle with high precision and under low background conditions. The helix provides excellent spatial resolution along with high counting rate performance and a resolution independent of the angle at which the particles enter the detector. (ERA citation 03:001330)