Probing nuclear effects with neutrino-induced charged-current neutral pion production

D Coplowe ,T Cai ,M Wospakrik ,A Ghosh ,Hang Su ,C N Nguyen ,F Akbar ,A Bravar ,Z Ahmad Dar ,H Da Motta ,C Wret ,R Fine ,J Félix ,J Kleykamp ,W A Mann ,D Last ,J T Sobczyk ,P A Rodrigues ,G N Perdue ,A Bashyal ,A Weber ,H Ray ,R Gran ,E Maher ,M Betancourt ,M Kordosky ,H Gallagher ,M A Ramírez ,J G Morfín ,L Fields ,A Filkins ,H Schellman ,S Manly ,J Miller ,A Bercellie ,G Barr ,D Ruterbories ,B Messerly ,O Altinok ,V Paolone ,S Henry ,A Bodek ,S Dytman ,X.-G Lu ,J K Nelson ,K S Mcfarland ,B Yaeggy ,R D Ransome ,A Norrick ,D Wark ,C J Solano Salinas ,D A Andrade ,A Lozano ,G Cáceres ,D Naples ,S Jena ,T Le ,M Sultana ,A M Gago ,C Mauger ,E Valencia ,H S Budd ,G A Díaz ,D A Harris ,M F Carneiro ,A Olivier ,V S Syrotenko ,L Zazueta

doi:10.1103/physrevd.102.072007

Abstract

We study neutrino-induced charged-current (CC) π0 production on carbon nuclei using events with fully imaged final-state proton-π0 systems. Novel use of final-state correlations based on transverse kinematic imbalance enables the first measurements of the struck nucleon’s Fermi motion, of the intranuclear momentum transfer (IMT) dynamics, and of the final-state hadronic momentum configuration in neutrino pion production. Event distributions are presented for (i) the momenta of neutrino-struck neutrons below the Fermi surface, (ii) the direction of missing transverse momentum characterizing the strength of IMT, and (iii) proton-pion momentum imbalance with respect to the lepton scattering plane. The observed Fermi motion and IMT strength are compared to the previous MINERνA measurement of neutrino CC quasielastic-like production. The measured shapes and absolute rates of these distributions, as well as the cross section asymmetries, show tensions with predictions from current neutrino generator models.1 MoreReceived 13 February 2020Accepted 28 September 2020Corrected 11 December 2020DOI:https://doi.org/10.1103/PhysRevD.102.072007Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.Published by the American Physical SocietyPhysics Subject Headings (PhySH)Research AreasNeutrino interactionsNucleus-neutrino interactionsParticle interactionsParticles & Fields

Highlights

In high-statistics neutrino oscillation experiments, the measurement precision of the fundamental properties of neutrinos is becoming limited by knowledge of neutrinonucleus interactions [1]
In NuWro, the effective spectral function (ESF) [56] incorporates the most important features of SF in generator implementation: in ESF, the probability distribution of the target nucleon momentum is identical to SF; for a selected value of the nucleon momentum, an average removal energy calculated from SF is used
This paper presents the first measurements of a set of novel final-state correlations in neutrino CC π0 production

Summary

INTRODUCTION

In high-statistics neutrino oscillation experiments, the measurement precision of the fundamental properties of neutrinos is becoming limited by knowledge of neutrinonucleus interactions [1]. MINERνA measured the final-state correlations in neutrino charged-current (CC) quasielastic (QE)-like interactions on carbon [6,7] These correlations are based on transverse kinematic imbalance (TKI) that helps precisely identify intranuclear dynamics [6,7,8,9,10,11,12,13,14,15] or the absence thereof [16,17,18,19,20]. Processes with intranuclear momentum transfer (IMT), such as final-state interactions (FSIs), pion absorption by the remnant, and production of extra particles included in X, will increase δαT; the resulting nonflatness in the δαT distribution indicates how much impedance the outgoing hadrons experience inside the nucleus [6,8,10]. This paper presents the first measurement of this new TKI

MEASUREMENT

RESULTS

SUMMARY