Two different nuclear-medium effects are isolated using a low three-momentum transfer subsample of neutrino-carbon scattering data from the MINERvA neutrino experiment. The observed hadronic energy in charged-current νµ interactions is combined with muon kinematics to permit separation of the quasielastic and ∆(1232) resonance processes. First, we observe a small cross section at very low energy transfer that matches the expected screening effect of long-range nucleon correlations. Second, additions to the event rate in the kinematic region between the quasielastic and ∆ resonance processes are needed to describe the data. The data in this kinematic region also has an enhanced population of multi-proton final states. Contributions predicted for scattering from a nucleon pair have both properties; the model tested in this analysis is a significant improvement but does not fully describe the data. We present the results as a double-differential cross section to enable further investigation of nuclear models. Improved description of the effects of the nuclear environment are required by current and future neutrino oscillation experiments.

Knowledge of the neutrino flux produced by the Neutrinos at the Main Injector (NuMI) beamline is essential to the neutrino oscillation and neutrino interaction measurements of the MINERvA, MINOS+, NOvA and MicroBooNE experiments at Fermi National Accelerator Laboratory. We have produced a flux prediction which uses all available and relevant hadron production data, incorporating measurements of particle production off of thin targets as well as measurements of particle yields from a spare NuMI target exposed to a 120 GeV proton beam. The result is the most precise flux prediction achieved for a neutrino beam in the one to tens of GeV energy region.We have also compared the prediction to in situ measurements of the neutrino flux and find good agreement.

Final-state kinematic imbalances are measured in mesonless production of ν_{μ}+A→μ^{-}+p+X in the MINERvA tracker. Initial- and final-state nuclear effects are probed using the direction of the μ^{-}-p transverse momentum imbalance and the initial-state momentum of the struck neutron. Differential cross sections are compared to predictions based on current approaches to medium modeling. These models underpredict the cross section at intermediate intranuclear momentum transfers that generally exceed the Fermi momenta. As neutrino interaction models need to correctly incorporate the effect of the nucleus in order to predict neutrino energy resolution in oscillation experiments, this result points to a region of phase space where additional cross section strength is needed in current models, and demonstrates a new technique that would be suitable for use in fine-grained liquid argon detectors where the effect of the nucleus may be even larger.

Charged pion production via charged-current νµ interactions on plastic scintillator (CH) is studied using the MINERvA detector exposed to the NuMI wideband neutrino beam at Fermilab. Events with hadronic invariant mass W < 1.4 GeV and W < 1.8 GeV are selected in separate analyses: the lower W cut isolates single pion production, which is expected to occur primarily through the ∆(1232) resonance, while results from the higher cut include the effects of higher resonances. Cross sections as functions of pion angle and kinetic energy are compared to predictions from theoretical calculations and generator-based models for neutrinos ranging in energy from 1.5-10 GeV. The data are best described by calculations which include significant contributions from pion intranuclear rescattering. These measurements constrain the primary interaction rate and the role of final state interactions in pion production, both of which need to be well understood by neutrino oscillation experiments.

Cross sections for ν_{μ} and ν[over ¯]_{μ} induced pion production on hydrocarbon in the few-GeV region using MINERvA FERMILAB-PUB-16-228-NDCross sections for ν µ andν µ induced pion production on hydrocarbon in the few-GeV region using MINERvA Separate samples of charged-current pion production events representing two semi-inclusive channels νµ-CC(π + ) andνµ-CC(π 0 ) have been obtained using neutrino and antineutrino exposures of the MINERvA detector. Distributions in kinematic variables based upon µ ± -track reconstructions are analyzed and compared for the two samples. The differential cross sections for muon production angle, muon momentum, and four-momentum transfer Q 2 , are reported, and cross sections versus neutrino energy are obtained. Comparisons with predictions of current neutrino event generators are used to clarify the role of the ∆(1232) and higher-mass baryon resonances in CC pion production and to show the importance of pion final-state interactions. For the νµ-CC(π + ) (νµ-CC(π 0 )) sample, the absolute data rate is observed to lie below (above) the predictions of some of the event generators by amounts that are typically 1-to-2 σ. However the generators are able to reproduce the shapes of the differential cross sections for all kinematic variables of either data set.