The AMS-02 Silicon Tracker: Status and Performances

Abstract

The Alpha Magnetic Spectrometer (AMS-02) is a space based high energy physics experiment operating on the International Space Station (ISS) since May. AMS-02 will measure the different cosmic radiation components allowing the search of primordial antimatter and dark matter annihilation products. Exploiting a large acceptance and a data taking of at least 10 years, AMS-02 will detect more than 1010 charged particles in the GV-TV rigidity range. The tracking device is composed by 2 planes at the ends of the apparatus and 7 layers of silicon sensors in the permanent magnet (0.15T) bore. The measurement of the curvature radius of the charged particles bent trajectories allows the estimation of particle rigidity and charge sign. The tracker is composed by 2264 double-sided silicon sensors (72x41 mm2 , 300 JJ.m thick) assembled in 192 read-out units, for a total of ~ 200.000 read-out channels. The status of the AMS-02 tracker, after these first months of data taking in space, its performances and potentialities will be presented.