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A Fourier-Based Algorithm for Modelling Aberrations in HETE-2's Imaging System

Bjoern Malte Schaefer·Nobuyuki Kawai
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Abstract

The High-Energy Transient Explorer (HETE-2), launched in October 2000, is a satellite experiment dedicated to the study of gamma-ray bursts in a very wide energy range from soft X-ray to gamma-ray wavelengths. The intermediate X-ray range (2-30keV) is covered by the Wide-field X-ray Monitor WXM, a coded aperture imager. In this article, an algorithm for reconstructing the positions of gamma-ray bursts is described, which is capable of correcting systematic aberrations to approximately 1 arcmin throughout the field of view. Functionality and performance of this algorithm have been validated using data from Monte Carlo simulations as well as from astrometric observations of the X-ray source Scorpius X-1.

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Bjoern Malte Schaefer, Nobuyuki Kawai. 2003-01-08. A Fourier-Based Algorithm for Modelling Aberrations in HETE-2's Imaging System. https://doi.org/10.1016/s0168-9002(03)00300-0

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