  We present a theoretical model for Bragg scattering from a Bose-Einstein
condensate (BEC) in the vicinity of a magnetic Feshbach resonance, using a two
c-field formalism, one c-field for the atom and the other for a molecule formed
of two atoms. We use this model to numerically simulate a recent experiment [S.
B. Papp et al., Phys. Rev. Lett., 101(13):135301, Sep 2008] investigating the
effects of strong interactions on the Bragg spectrum from a 85Rb BEC. Results
from these simulations are in very good quantitative agreement with the
experimental results, confirming the importance of the resonance bound state in
the dynamics of the condensate for fast experiments like Bragg scattering.
