  The most intense gamma-ray line observable from novae is likely to be from
positron annihilation associated with the decay of 18F. The uncertainty in the
destruction rate of this nucleus through the 18F(p,{\alpha})15O reaction
presents a limit to interpretation of any future observed gamma-ray flux.
Direct measurements of the cross section of both this reaction and the
18F(p,p)18F reaction have been performed between center of mass energies of 0.5
and 1.9 MeV. Simultaneous fits to both data sets with the R-Matrix formalism
reveal several resonances, with the inferred parameters of populated states in
19Ne in general agreement with previous measurements. Of particular interest,
extra strength has been observed above ECM \sim1.3 MeV in the 18F(p,p)18F
reaction and between 1.3-1.7 MeV in the 18F(p,{\alpha})15O reaction. This is
well described by a broad 1/2+ state, consistent with both a recent theoretical
prediction and an inelastic scattering measurement. The astrophysical
implications of a broad sub-threshold partner to this state are discussed.
