The AMS-02 silicon tracker: First year on ISS in space

The AMS-02 particle physics experiment was installed on the International Space Station in May 2011 and is taking cosmic ray data since then. Its tracker, with a total active area of 6.75 m(2), is made of silicon microstrips detectors in the field of a permanent magnet. It measures the rigidity and charge sign and identifies the ion species by dE/dx. The status of the AMS-02 tracker and its operation, after first months of data taking in space, is presented, as well as its performances and potentialities. (C) 2012 Elsevier B.V. All rights reserved.