Applications of pixellated GaAs X-ray detectors in a synchrotron radiation beam

Watt, J. , Bates, R., Campbell, M., Mathieson, K., Mikulec, B., O'Shea, V. , Passmore, M.S., Schwarz, C., Smith, K.M. and Whitehill, C. (2001) Applications of pixellated GaAs X-ray detectors in a synchrotron radiation beam. Nuclear Instruments and Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment, 460(1), 185 -190. (doi: 10.1016/S0168-9002(00)01112-8)

Abstract

Hybrid semiconductor pixel detectors are being investigated as imaging devices for radiography and synchrotron radiation beam applications. Based on previous work in the CERN RD19 and the UK IMPACT collaborations, a photon counting GaAs pixel detector (PCD) has been used in an X-ray powder diffraction experiment. The device consists of a 200 mum thick SI-LEC GaAs detector patterned in a 64 x 64 array of 170 mum pitch square pixels, bump-bonded to readout electronics operating in single photon counting mode. Intensity peaks in the powder diffraction pattern of KNbO3 have been resolved and compared with results using the standard scintillator, and a PCD predecessor (the Ohm3). The PCD shows improved speed, dynamic range, 2-D information and comparable spatial resolution to the standard scintillator based systems. It also overcomes the severe dead time limitations of the Ohm3 by using a shutter based acquisition mode. A brief demonstration of the possibilities of the system for dental radiography and image processing are given, showing a marked reduction in patient dose and dead time compared with film.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: O'Shea, Professor Val and Mathieson, Dr Keith and Watt, Dr John and Bates, Dr Richard
• Authors: Watt, J., Bates, R., Campbell, M., Mathieson, K., Mikulec, B., O'Shea, V., Passmore, M.S., Schwarz, C., Smith, K.M., and Whitehill, C.
• Subjects: Q Science > QC Physics
• College/School: College of Science and Engineering > School of Physics and Astronomy; University Services > IT Services > E-Science
• Journal Name: Nuclear Instruments and Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment
• Publisher: Elsevier BV
• ISSN: 0168-9002
• ISSN (Online): 1872-9576
• Published Online: 09 March 2001