Unique Properties of Secondary Cosmic Rays: Results from the Alpha Magnetic Spectrometer

We present high-statistics measurements of the secondary cosmic rays Lithium, Beryllium, Boron, and Fluorine based on 11.5 years of AMS data. The unexpected rigidity dependence of the secondary cosmic ray fluxes and their ratios to the primary cosmic rays such as Li/C, Be/C, B/C, Li/O, Be/O, B/O, F/Si and P/Si are discussed. The systematic comparison with the latest GALPROP cosmic ray model is also presented.