Measurement of single ${\pi }^0$ production by coherent neutral-current $\nu$ Fe interactions in the MINOS Near Detector

Forward single ${\pi }^0$ production by coherent neutral-current interactions, $\nu \mathcal{A}\to \nu \mathcal{A}{\pi }^0$, is investigated using a 2.8$\times 10^{20}$ 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 $\langle $\mathcal{A}$ \rangle = 48$,thehighest-$\langle $\mathcal{A}$ \rangle$ target used to date in the study of this coherent reaction. The total cross section for coherent neutral-current single-${\pi }^0$ production initiated by the ${\nu }_{\mu }$ flux of the NuMI low-energy beam with mean (mode) $E_{\nu }$ of 4.9 GeV (3.0 GeV), is $77.6\pm5.0,($\text{stat}$) ^{+15.0}_{-16.8},($\text{syst}$)\times10^{-40},$\text{cm}$^2~$\text{per nucleus}$$. The results are in good agreement with predictions of the Berger-Sehgal model.