  Light ion (A<5) breakup cross sections are important for studies of cosmic
ray interactions in the inter-stellar medium or radiation protection
considerations of energy deposition in tissue. Nucleon abrasion cross sections
for heavy ion reactions are often calculated using the Glauber model in the
large mass limit or with the Eikonal form of the optical potential model. Here
we formulate an abrasion model for 4He nuclei fragmentation on hydrogen targets
with a classical model for final state interactions. Comparisons to the heavy
ion abrasion model are made. Calculations of energy dependent total,
absorption, elastic and breakup cross sections for 4He into 3He or 3H with
protons targets are shown to be in good agreement with experimental
measurements for energies from 100 to 100,000 MeV/u. The Glauber model for
light nuclei and the large mass limit to the model are shown to be in close
agreement for 4He-proton interactions above 300 MeV/u, however important
differences occur at lower energies.
