Constraining $\nu$-Process Production of Fluorine through Cosmic Ray
  Nucleosynthesis
  Fluorine is massive enough that it is not considered to be a light ($Z\le5$)
element, yet compared to its near neighbors, C, N, O, and Ne, it is far
underproduced in the course of stellar evolution, making its origin more
complex. In fact, the abundance of fluorine is the lowest among all elements
between Z = 5 and 21 and is roughly 3-4 orders of magnitude below that of C, N,
O, and Ne. There are several plausible sources for F beyond standard stellar
evolution. These include the production in the asymptotic giant branch phase
(AGB) in intermediate mass stars, production in Wolf-Rayet stars, and the
production through neutrino spallation in supernovae. The latter, known as the
$\nu$-process, is an important source for B11, and may contribute to the
abundance of Li7 as well. We combine a simple model of Galactic chemical
evolution with a standard Galactic cosmic ray nucleosynthesis model to treat
self-consistently the evolution of the Li, Be, and B isotopes. We include
massive star production of F, as well as contributions from AGB stars, and the
$\nu$-process. Given the uncertainties in neutrino energies in supernovae, we
normalize the $\nu$-process using the observed B11/B10 ratio as a constraint.
As a consequence, we are able to determine the relative importance of each
contribution to the F abundance. We find that although the $\nu$-process
dominates at early times (low metallicity), the present-day F abundance is
found to originate primarily from AGB stars.
