Measurement of single π0 production by coherent neutral-current ν Fe interactions in the MINOS Near Detector

Forward single π^0 production by coherent neutral-current interactions, νA→νAπ^0, is investigated using a 2.8×10^(20) protons-on-target exposure of the MINOS Near Detector. For single-shower topologies, the event distribution in production angle exhibits a clear excess above the estimated background at very forward angles for visible energy in the range 1–8 GeV. Cross sections are obtained for the detector medium comprised of 80% iron and 20% carbon nuclei with ⟨A⟩=48, the highest-⟨A⟩ target used to date in the study of this coherent reaction. The total cross section for coherent neutral-current single π^0 production initiated by the ν_μ flux of the NuMI low-energy beam with mean (mode) E_ν of 4.9 GeV (3.0 GeV), is 77.6±5.0(stat)^(+15.0)_(−16.8)(syst)×10^(−40)  cm^2 pernucleus. The results are in good agreement with predictions of the Berger-Sehgal model.