  Solar flare observations are used to demonstrate the new technique of
abundance determination based on gamma ray line emission produced by
accelerated particle bombardment. Some of the implications of similar gamma ray
line emission observed from Orion, including the production of light elements
by low energy cosmic rays, are reviewed.
  For such an origin for the light elements, limitations on the total available
energy in low energy cosmic rays imply that the production takes place at
relatively high particle energies, around 30 MeV/nucl. Such low energy cosmic
rays can reproduce the meteoritic B isotopic ratio of 4, but they require an
accelerated C/O on the order of the observed solar system ratio ($\sim$0.5). If
in the early Galaxy C/O in the ejecta of Type II supernovae from massive star
progenitors (which are thought to be the sources of the postulated cosmic rays)
is much lower, then the B isotopic ratio in low metallicity stars should be
significantly lower than the measured meteoritic value.

Astrophysics