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  • K. S. K. Lum, R. P. Manandhar, S. S. Eikenberry, M. Krockenberger, and J. E. Grindlay
  • Harvard-Smithsonian Center for Astrophysics
  • 60 Garden Street
  • Cambridge, Massachusetts 02138
    "Initial Performance of the EXITE2 Imaging Phoswich Detector/Telescope for Hard X-ray Astronomy"

    Paper published in IEEE Trans. Nucl. Sci., NS-41, 1354-1363 (1994):

    We have developed, tested, and flown a large-area imaging phoswich detector/telescope for hard X-ray astronomy. This second-generation Energetic X-ray Imaging Telescope Experiment (EXITE) is designed to detect and image cosmic X-ray sources in the 20-600 keV energy range from a high-altitude balloon. Imaging is accomplished via the coded-aperture technique. Laboratory tests have shown that the detector achieves 14% (FWHM) energy resolution and ~ 10 mm (FWHM) spatial resolution at 60 keV, and that the pulse-shape discrimination (PSD) circuit effectively distinguishes between NaI(Tl) and CsI(Na) events from ~ 40-400 keV. The first flight of the instrument was from Palestine, Texas, on 13-14 June 1993. In this paper, we present details of the laboratory performance of the system and some flight results.