We have investigated electroluminescence (EL) detectors with uniform and axial electric field configurations, filled with xenon gas pressurized up to 35 bar. Photomultipliers placed outside pressurized vessels and avalanche photodiodes placed directly inside the pressurized xenon have been used to detect scintillation and electroluminescence signals. A light-collection system based on a cylindrical array of wavelength shifting fibers has been used to collect light in the detector with axial electric field. The EL detectors with photomultiplier readout have demonstrated exceptionally low sensitivity to vibrations. An energy resolution of 10%FWHM was measured for 60 keV gamma rays. The results are discussed and measures that will be undertaken to improve performance of the detectors are considered.
New approaches to the design of high-pressure Xe (HPXe) ionization chambers are described. HPXe ionization chambers represent a well-known technique for detecting gamma rays in the energy range between 50 keV and 3 MeV. Since the HPXe detector is an electron-only carrier device, its commonly accepted design includes a Frisch-grid-a metal mesh employed for the electrostatic shielding from the immobile positive ions. The grid is a key element of the device’s design which provides good energy resolution of the detector, typically 2-3% FWHM at 662 keV. However, the grid makes the design more complex and less rugged, especially for field applications. Recently, we developed several designs of HPXe ionization chambers without shielding grids. The results obtained from the testing of these devices are presented here.
Conference Committee Involvement (1)
Hard X-Ray and Gamma-Ray Detector Physics VII
1 August 2005 | San Diego, California, United States