The anti matter spectrometer (AMS-02): a particle physics detector in space

AMS-02 is a space borne magnetic spectrometer designed to measure with accuracies up to one part in 109 the composition of Cosmic Rays near Earth. With a large acceptance (5000 cm2 sr), an intense magnetic field from a superconducting magnet (0.7 T) and an accurate particle identifications AMS-02 will provide the highest accuracy in Cosmic Rays measurements up to the TeV region. During a three years long mission on the ISS AMS-02 will achieve a sensitivity to the existence of anti-He in the Cosmic Rays of one part in a billion as well as important informations on the origin of Dark Matter. We review the status of the construction of the AMS-02 experiment in preparation for the three years mission on the ISS.