  Neutron-capture reactions on $^{18}$F in the helium-burning shell play an
important role in the production of $^{15}$N during core-collapse supernovae.
The competition between the $^{18}$F($n,p/\alpha$)$^{18}$O/$^{15}$N reactions
controls the amount of $^{15}$N produced. The strengths of these reactions
depend on the decay branching ratios of states in $^{19}$F above the neutron
threshold. We report on an experiment investigating the decay branching ratios
of these states in order to better constrain the strengths of the reactions.
