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This paper seeks to find an explanation of the galactic cosmic ray B/C rationewly measured in cosmic rays between ~10 MeV/nuc and 1 TeV/nuc. Voyagermeasurements of this ratio at low energies and AMS-2 measurements at highenergies are used in this study. These measurements both considerably exceed atboth low and high energies the ratio predicted using a simple Leaky Box Modelfor propagation of cosmic rays in the galaxy. Between 1-70 GeV/nuc, however,this same model provides an excellent fit (within +2-3%) to the new AMS-2measurements using an escape length ~P-0.45. This would imply a diffusioncoefficient ~P0.45, very close to the Kraichian cascade value of 0.50 for theexponent. Extending this same diffusion dependence to high energies, still in aLBM, along with a truncation of short path lengths in the galaxy will predict aB/C ratio of 4.5% at ~800 GeV/nuc which is very close to the AMS-2 measurementat that energy. This would indicate that the amount of material traversed nearthe source in a Nested LBM, for example, is less than about 0.5 g/cm2 at theseenergies since this process, with additional matter near the sources, wouldincrease the B/C ratio. At low energies, however, the B/C ratio of 14% +3% at~10 MeV/nuc measured by Voyager is more difficult to explain. The sameparameters used in a LBM that fit the high energy B/C measurements predicts aB/C ratio of only ~4% at 10 MeV/nuc where the path length is about 1.5 g/cm2.If the cosmic rays have traversed ~10 g/cm2 of material in the galaxy at lowenergies the prediction for B/C is still only 8%, which is between 2.0-3.0sigma below the measurement and its errors.

A Study of the B/C Ratio Between 10 MeV/nuc and 1 TeV/nuc in Cosmic Rays  Using New Voyager and AMS-2 Data and a Comparison with the Predictions of  Leaky Box Propagation Models