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Multiscale image analysis applied to gamma/hadron discrimination for VHE gamma-ray astronomy with ARGO-YBJ

I. De Mitri·G. Marsella·F. Salamida
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Abstract

Intrinsic differences in the processes involved in the development of electromagnetic and hadronic showers in the atmosphere have been evidenced by means of a careful analysis of the event image given by the ARGO-YBJ detector. The images have been analyzed at different length scales and their multifractal nature has been studied. The use of the multiscale approach together with a properly designed and trained Artificial Neural Network, allowed us to obtain a good gamma/hadron discrimination power. If confirmed by further studies on different event cathegories, this result would allow to nearly double the detector sensitivity to gamma ray sources.

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I. De Mitri, G. Marsella, F. Salamida. 2003-07-30. Multiscale image analysis applied to gamma/hadron discrimination for VHE gamma-ray astronomy with ARGO-YBJ. https://doi.org/10.1016/j.nima.2004.03.052

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