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arXiv · 0710.2428

The anomaly in the cosmic-ray positron spectrum

C. H. Chung·H. Gast·J. Olzem·S. Schael
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Abstract

A recent analysis of cosmic-ray data from a space borne experiment by the AMS collaboration supports the observation of an excess in the cosmic-ray positron spectrum by previous balloon experiments. The combination of the various experimental data establishes a deviation from the expected background with a significance of more than four standard deviations. The observed change in the spectral index cannot be explained without introducing a new source of positrons. When interpreted within the MSSM a consistent description of the antiproton spectrum, the diffuse gamma-ray flux and the positron fraction is obtained which is compatible with all other experimental data, including recent WMAP data.

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C. H. Chung, H. Gast, J. Olzem, S. Schael. 2007-10-12. The anomaly in the cosmic-ray positron spectrum. https://arxiv.org/abs/0710.2428

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