Faced with unresolved tensions between neutrino interaction measurements at few-GeV neutrino energies, current experiments are forced to accept large systematic uncertainties to cover discrepancies between their data and model predictions. The widely used pion production model in genie is compared to four MINERνA charged current pion production measurements using nuisance. Tunings, i.e., adjustments of model parameters, to help match genie to MINERνA and older bubble chamber data are presented. We find that scattering off nuclear targets as measured in MINERνA is not in good agreement with expectations based upon scattering off nucleon (hydrogen or deuterium) targets in existing bubble chamber data. An additional ad hoc correction for the low-Q2 region, where collective nuclear effects are expected to be large, is presented. While these tunings and corrections improve the agreement of genie with the data, the modeling is imperfect. The development of these tunings within the nuisance framework allows for straightforward extensions to other neutrino event generators and models, and allows omitting and including new datasets as they become available.
Bibliographical noteFunding Information:
P. S., L. P., and C. Wret would like to thank the UK Science and Technology Facilities Council (STFC) for Ph.D. funding support. P. S. acknowledges the Fermilab Neutrino Physics Center for the scholarship that funded this work and thanks Fermilab and the Collaboration for their hospitality during this work. C. Wilkenson acknowledges the support of the Swiss National Science Foundation and SERI. This document was prepared by members of the Collaboration using the resources of the Fermi National Accelerator Laboratory (Fermilab), a U.S. Department of Energy, Office of Science, HEP User Facility. Fermilab is managed by Fermi Research Alliance, LLC (FRA), acting under Contract No. DE-AC02-07CH11359. These resources included support for the construction project, and support for construction also was granted by the U.S. National Science Foundation under Grant No. PHY-0619727 and by the University of Rochester. Support for participating scientists was provided by NSF and DOE (USA); by CAPES and CNPq (Brazil); by CoNaCyT (Mexico); by Proyecto Basal FB 0821, CONICYT PIA ACT1413, Fondecyt 3170845, and 11130133 (Chile); by CONCYTEC, Dirección de Gestión de la Investigación—Pontificia Universidad Católica del Perú (DGI-PUCP), and Vicerrectorado de Investigación-Universidad Nacional de Ingeniería (VRI-UNI) (Peru); and by the Latin American Center for Physics (CLAF); NCN Opus Grant No. 2016/21/B/ST2/01092 (Poland). We thank the MINOS Collaboration for use of its near detector data. Finally, we thank the staff of Fermilab for support of the beam line, the detector, and the computing infrastructure.
© 2019 authors. Published by the American Physical Society.