An improved technique of image analysis for IACTs and IACT Systems

M. Ulrich; A. Daum; G. Hermann; W. Hofmann

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arXiv · astro-ph/9708003

An improved technique of image analysis for IACTs and IACT Systems

M. Ulrich·A. Daum·G. Hermann·W. Hofmann

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Abstract

In order to better utilize the information contained in the shower images generated by imaging Cherenkov telescopes (IACTs) equipped with cameras with small pixels, images are fit to a parametrization of image shapes gained from Monte Carlo simulations, treating the shower direction, impact point, and energy as free parameters. Monte Carlo studies for a system of IACTs predict an improvement of order 1.5 in the angular resolution. The fitting technique can also be applied to single-telescope images; simulations indicate that the shower direction in space can be reconstructed event-by-event with a resolution of 0.16 deg. to 0.20 deg., allowing to generate genuine source maps. Data from Crab observations with a single HEGRA telescope confirm this prediction.

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M. Ulrich, A. Daum, G. Hermann, W. Hofmann. 1997-08-01. An improved technique of image analysis for IACTs and IACT Systems. https://arxiv.org/abs/astro-ph/9708003

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