CCQE, 2p2h excitations and \nu-energy reconstruction

TL;DR

This paper demonstrates that including nuclear effects like RPA correlations and 2p2h mechanisms is crucial for accurately modeling MiniBooNE muon neutrino CCQE-like data, reconciling the axial mass with previous measurements and highlighting issues in energy reconstruction.

Contribution

The study introduces a comprehensive theoretical model incorporating RPA and 2p2h effects, clarifying the axial mass value and exposing artifacts in neutrino energy unfolding.

Findings

Nuclear effects are essential for data description.

MiniBooNE data compatible with M_A ~ 1.05 GeV.

Unfolded cross section artifacts due to 2p2h neglect.

Abstract

We analyze the MiniBooNE muon neutrino CCQE-like d\sigma/dT_\mu/dcos\theta_\mu data using a theoretical model that, among other nuclear effects, includes RPA correlations and 2p2h (multinucleon) mechanisms. These corrections turn out to be essential for the description of the data. We find that MiniBooNE CCQE-like data are fully compatible with former determinations of the nucleon axial mass M_A ~ 1.05 GeV. This is in sharp contrast with several previous analysis where anomalously large values of M_A ~ 1.4 GeV have been suggested. We also show that because of the the multinucleon mechanism effects, the algorithm used to reconstruct the neutrino energy is not adequate when dealing with quasielastic-like events. Finally, we analyze the MiniBooNE unfolded cross section, and show that it exhibits an excess (deficit) of low (high) energy neutrinos, which is an artifact of the unfolding process that ignores 2p2h mechanisms.