Neutrino-Induced Coherent π^{+} Production in C, CH, Fe, and Pb at ⟨E_{ν}⟩∼6  GeV.

MINERvA has measured the ν&#95;{μ}-induced coherent π^{+} cross section simultaneously in hydrocarbon (CH), graphite (C), iron (Fe), and lead (Pb) targets using neutrinos from 2 to 20 GeV. The measurements exceed the predictions of the Rein-Sehgal and Berger-Sehgal PCAC based models at multi-GeV ν&#95;{μ} energies and at produced π^{+} energies and angles, E&#95;{π}>1  GeV and θ&#95;{π}<10°. Measurements of the cross-section ratios of Fe and Pb relative to CH reveal the effective A scaling to increase from an approximate A^{1/3} scaling at few GeV to an A^{2/3} scaling for E&#95;{ν}>10  GeV.