Gamma-Ray Imaging with the Coded Mask IBIS Telescope

TL;DR

The paper details the design, imaging principles, and data analysis procedures of the IBIS telescope's coded mask system for gamma-ray sky imaging onboard the INTEGRAL mission.

Contribution

It introduces the basic concepts, imaging system, and standard data analysis procedures for the IBIS telescope's coded mask gamma-ray imaging.

Findings

Development of iterative decoding procedures for shadowgram analysis

Implementation plan for IBIS data analysis software

Description of the imaging system's capabilities and limitations

Abstract

The IBIS telescope onboard INTEGRAL, the ESA gamma-ray space mission to be launched in 2002, is a soft gamma-ray (20 keV - 10 MeV) device based on a coded aperture imaging system. We describe here basic concepts of coded masks, the imaging system of the IBIS telescope, and the standard data analysis procedures to reconstruct sky images. This analysis includes, for both the low-energy detector layer (ISGRI) and the high energy layer (PICSIT), iterative procedures which decode recorded shadowgrams, search for and locate sources, clean for secondary lobes, and then rotate and compose sky images. These procedures will be implemented in the Quick Look and Standard Analysis of the INTEGRAL Science Data Center (ISDC) as IBIS Instrument Specific Software.