  We report on multinucleon effects in low momentum transfer ($< 0.8$ GeV/c)
anti-neutrino interactions on plastic (CH) scintillator. These data are from
the 2010-2011 antineutrino phase of the MINERvA experiment at Fermilab. The
hadronic energy spectrum of this inclusive sample is well described when a
screening effect at low energy transfer and a two-nucleon knockout process are
added to a relativistic Fermi gas model of quasielastic, $\Delta$ resonance,
and higher resonance processes. In this analysis, model elements introduced to
describe previously published neutrino results have quantitatively similar
benefits for this antineutrino sample. We present the results as a
double-differential cross section to accelerate investigation of alternate
models for antineutrino scattering off nuclei.
