Measurement of νμ charged-current single π0 production on hydrocarbon in the few-GeV region using MINERvA

Abstract

The semi-exclusive channel νµ +CH → µ − π 0 +nucleon(s) is analyzed using MINERvA exposed to the low-energy NuMI νµ beam with spectral peak at Eν 3 GeV. Differential cross sections for muon momentum and production angle, π 0 kinetic energy and production angle, and for squared fourmomentum transfer are reported, and the cross section σ(Eν ) is obtained over the range 1.5 GeV ≤ Eν < 20 GeV. Results are compared to GENIE and NuWro predictions and to published MINERvA cross sections for charged current π + (π 0 ) production by νµ(νµ) neutrinos. 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 π 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 π 0 mesons, the pπ 0 invariant mass distribution is obtained, and the decay polar and azimuthal angle distributions in the rest frame of the pπ 0 system are measured in the region of ∆(1232) + production, W < 1.4 GeV.

Pion-proton correlation in neutrino interactions on nuclei

“…With a deuterium target, ANL reported A LR = 0.053 ± 0.035 of π + in reaction (1) with a neutrino beam energy distribution that peaked near 0.9 GeV [16]. In 2017, MINERvA reported A LR = 0.15 ± 0.10 of π 0 in the pπ 0 rest frame from reaction (2) on a hydrocarbon target at the Low-Energy NuMI beam with peak energy about 3 GeV [11]. These asymmetries indicate the polarized production of resonances, dominated by ∆(1232), and are ascribed to the interference between the resonant and nonresonant amplitudes [17][18][19][20].…”

“…Their experimental evidence is the otherwise unaccounted for measured excess of event rates [8,9]. Complementary to the 0π topology, pion production [10,11] has provided important constraints on both primary pion production and pion FSIs (cf. for example, Ref.…”

Measurement of ν¯μ charged-current single π− production on hydrocarbon in the few-GeV region using MINERvA

“…[42]. Additional details concerning GENIE modeling of CC(π) channels are given in MINERvA publications [11][12][13]. Recent developments in neutrino phenomenology motivate certain augmentations to GENIE that are implemented via event reweighting and by adding a simulated sample of quasielastic-like 2-particle 2-hole (2p2h) events [44].…”

“…Recent developments in neutrino phenomenology motivate certain augmentations to GENIE that are implemented via event reweighting and by adding a simulated sample of quasielastic-like 2-particle 2-hole (2p2h) events [44]. The refinements (described below) are very similar to those used in the reference simulations of recent, published MINERvA measurements [8,13,42,[45][46][47][48][49]. Importantly, all refinements to the GENIE-based MC used here (version designation MnvGENIE v1.2) were decided prior to the present work, and the data analyzed here were not used in the GENIE tuning.…”

“…These differential cross sections complement and extend MIN-ERvA's previously reported measurements of CC pion production on hydrocarbon. The latter measurements includeν µ -induced CC(1π 0 ) production [10,11], and ν µinduced CC(π + ) and CC(1π 0 ) production [11][12][13].…”