First Results of the AMS-02 Experiment on the ISS

The Alpha Magnetic Spectrometer has recently released a first set of precise measurements on the cosmic rays detected from the International Space Station. The results on the positron fraction in the energy range from 0.5 to 350GeV and the search for positron anisotropy are summarized. The very accurate data show that the positron fraction is steadily increasing from 10 to similar to 250 GeV. The positron fraction spectrum shows no fine structure and the positron to electron ratio shows no observable anisotropy. This is not consistent with only the secondary production of positrons. The parametrization of the positron fraction and the e(+) + e(-) flux measurements within the framework of a minimal model provides a complete description of the positron source contribution. The predictions for different scenarios accounting for the positron source component can thus be directly compared to this measurement.