The semi-exclusive channel $\nu_{ \mu}+\textrm{ CH}\rightarrow\mu^{ -}\pi^{ 0}+\textrm{ nucleon(s)}$ is analyzed using MINERvA exposed to the low-energy NuMI $\nu_{ \mu}$ beam with spectral peak at $E_{ \nu} \simeq 3$ GeV. Differential cross sections for muon momentum and production angle, $\pi^{ 0}$ kinetic energy and production angle, and for squared four-momentum transfer are reported, and the cross section $\sigma(E_{ \nu})$ is obtained over the range 1.5 GeV $\leq E_{ \nu} <$ 20 GeV. Results are compared to GENIE and NuWro predictions and to published MINERvA cross sections for $\nu_{ \mu}\textrm{ -CC}(\pi^{ +})$ and $\bar{ \nu}_{ \mu}\textrm{ -CC}(\pi^{ 0})$. Disagreements between data and simulation are observed at very low and relatively high values for muon angle and for $Q^2$ that may reflect shortfalls in modeling of interactions on carbon. For $\pi^{ 0}$ kinematic distributions however, the data are consistent with the simulation and provide support for generator treatments of pion intranuclear scattering. Using signal-event subsamples that have reconstructed protons as well as $\pi^{ 0}$ mesons, the $p\pi^{ 0}$ invariant mass distribution is obtained, and the decay polar and azimuthal angle distributions in the rest frame of the $p\pi^{ 0}$ system are measured in the region of $\Delta(1232)^+$ production, $W < 1.4$ GeV.
Categories: hep-ex