The anomaly in the cosmic-ray positron spectrum

TL;DR

This paper discusses the confirmed excess in cosmic-ray positrons observed by multiple experiments, suggesting a new source of positrons, and interprets the findings within the MSSM framework consistent with various astrophysical data.

Contribution

It provides a combined analysis of cosmic-ray positron data confirming the excess and offers a theoretical interpretation within the MSSM model.

Findings

Significant deviation in positron spectrum observed

Consistency with MSSM interpretation

Compatible with gamma-ray and antiproton data

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.