The Alpha Magnetic Spectrometer silicon tracker

The Alpha Magnetic Spectrometer is designed to operate on the International Space Station for a long duration measurement of the cosmic-ray spectra in the energy range between 0.5 GeV and several TeV. The particle rigidity and specific energy loss are measured by a silicon tracker located in a 0.8 T field. The tracker is described and selected performance results from the assembly phase and particle beam measurements are reported.