Scaling limit of a nonrelativistic model of confined "quarks"

I calculate the structure function for scattering from the two-body bound state in its lowest level in a nonrelativistic model of confined scalar "quarks" of masses $m_A$ and $m_B$. The scaling limit in $x=\frac{{\mathrm{q}}^2}{2(m_A+m_B)q^0}$ exists and is nonvanishing only for the values $x=\frac{m_A}{(m_A+m_B)}$ and $x=\frac{m_B}{(m_A+m_B)}$ which correspond to the fractions of the momentum of the two-body system carried by each of the "quarks." In the scaling limit, the interference from scattering off of the two "quarks" vanishes. Thus the scaling limit of this model agrees with the parton picture.