  For kink-antikink scattering within the \phi^4 non--linear field theory in
one space and one time dimension resonance type configurations emerge when the
relative velocity between kink and antikink falls below a critical value. It
has been conjectured that the vibrational excitation of the kink would be the
source for these resonances because (simplified) collective coordinate
calculations, that emphasized on this excitation, qualitatively reproduced
those resonances. Surprisingly a numerical study in the \phi^6 field theory
also exhibited such resonances even though it does not contain the vibrational
excitation. To explore this contradiction we start from the working hypothesis
that in either model any collective coordinate ansatz which includes a degree
of freedom similar to the vibrational excitation leads to resonances,
regardless of whether or not this mode emerges as a solution to the
(linearized) field equations. To this end we compare numerical results in the
\phi^4 and \phi^6 models that arise from the full set of partial differential
equations to those from the ordinary differential equations for a collective
coordinate ansatz. An inaccuracy in literature formulas for the collective
coordinate approach in the \phi^4 model requires to revisit those calculations.
