Preliminary Results from the 1999 Balloon Flight of the Liquid Xenon Gamma-Ray Imaging Telescope (LXeGRIT)

E. Aprile; U. G. Oberlack; A. Curioni; V. Egorov; K. -L. Giboni; ; S. Ventura; ; T. Doke; J. Kikuchi; K. Takizawa; ; E. L. Chupp; P. P. Dunphy

doi:10.1117/12.409128

arXiv · astro-ph/0012398

Preliminary Results from the 1999 Balloon Flight of the Liquid Xenon Gamma-Ray Imaging Telescope (LXeGRIT)

E. Aprile·U. G. Oberlack·A. Curioni·V. Egorov·K. -L. Giboni·; S. Ventura·; T. Doke·J. Kikuchi·K. Takizawa·; E. L. Chupp·P. P. Dunphy

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Abstract

LXeGRIT is a balloon-borne Compton telescope employing a large volume liquid xenon time projection chamber (LXeTPC) as the central gamma-ray detector. It is designed to image gamma rays in the energy range of 200 keV to 20 MeV, with an angular resolution of about 3 degrees (1 sigma) at 2 MeV, within a field-of-view (FOV) of about 1 sr. The detector's energy and three-dimensional spatial resolution as measured during pre-flight calibration experiments, are $ΔE_\mathrm{lxe}/E=8.8% : \sqrt{1\MeV /E}$ and < 1mm RMS, respectively. The detection efficiency for Compton events varies between 1.5% and 4% depending on energy and event selection. We describe the instrument as flown on May 7, 1999 and review its overall performance at balloon altitude. The launch occurred at 13:26:54 UT from Ft. Sumner, New Mexico and the flight was terminated about 9 hours later. The Crab was in the instrument FOV for a few hours. Analysis of these data is in progress.

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E. Aprile, U. G. Oberlack, A. Curioni, V. Egorov, K. -L. Giboni, ; S. Ventura, ; T. Doke, J. Kikuchi, K. Takizawa, ; E. L. Chupp, P. P. Dunphy. 2000-12-19. Preliminary Results from the 1999 Balloon Flight of the Liquid Xenon Gamma-Ray Imaging Telescope (LXeGRIT). https://doi.org/10.1117/12.409128

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