Measurement of the cosmic $e^{+} + e^{-}$ Flux from 0.5 GeV to 1 TeV with the Alpha Magnetic Spectrometer (AMS-02) on the International Space Station

The measurement of positrons and electrons (e+/-) in cosmic rays provides fundamental information about the origin and the propagation of cosmic rays in the Galaxy. The interest in the e measurements is enhanced by the possibility to observe indirect evidences of Dark Matter annihilation in the e spectral shapes and arrival directions. The most precise space experiment for the detection of cosmic rays is the Alpha Magnetic Spectrometer (AMS). AMS is a large acceptance cosmic ray detector which has been installed on the International Space Station in May 2011 to conduct an unique long-duration ( ~20 years) mission of fundamental physics research in space. In this thesis, the events collected by AMS in the first 30 months of data taking have been analyzed to measure the (e+ + e􀀀-) energy spectrum. A total of 10.6 million events have been identified as e+/- and have been used for the measurement of the (e+ + e-􀀀) flux from 0.5 GeV to 1 TeV. In this thesis the AMS detection capabilities, the e+/- identification procedure, the (e+ +e􀀀-) flux measurement, and the discussion of the result are presented.