Characterization of nuclear effects in muon-neutrino scattering on hydrocarbon with a measurement of final-state kinematics and correlations in charged-current pionless interactions at T2K

This paper reports measurements of final-state proton multiplicity, muon and proton kinematics, and their correlations in charged-current pionless neutrino interactions, measured by the T2K ND280 near detector in its plastic scintillator (C$_8$H$_8$) target. The data were taken between years 2010 and 2013, corresponding to approximately 6$\times10^{20}$ protons on target. Thanks to their exploration of the proton kinematics and of kinematic imbalances between the proton and muon kinematics, the results offer a novel probe of the nuclear-medium effects most pertinent to the (sub-)GeV neutrino-nucleus interactions that are used in accelerator-based long-baseline neutrino oscillation measurements. These results are compared to many neutrino-nucleus interaction models which all fail to describe at least part of the observed phase space. In case of events without a proton above a detection threshold in the final state, a fully consistent implementation of the local Fermi gas model with multinucleon interactions gives the best description of the data. In the case of at least one proton in the final state the spectral function model agrees well with the data, most notably when measuring the kinematic imbalance between the muon and the proton in the plane transverse to the incoming neutrino. A clear indication of existence of multinucleon interactions is observed. The effect of final-state interactions is also discussed.

本文报告了最终状态质子多样性，MUON和质子运动学的测量，及其在带电的无pionless中微子相互作用中的相关性，由T2K ND280在其塑料scintillator（C $ _8 $ H $ _8 $）目标中测量。数据是在2010年至2013年之间进行的，对应于目标上的6 $ \ times10^{20} $质子。多亏了他们探索质子运动学以及质子和MUON运动学之间的运动学失衡，结果提供了一种新颖的探测核中核作用最相关的核中性核核相互作用，这些效应用于Accelerator-nucleus - Accelerator--基于长基线中微子振荡测量。将这些结果与许多中微子核相互作用模型进行比较，这些模型都无法描述至少一部分观察到的相空间。如果在最终状态下没有质子的事件没有质子的检测阈值，则具有Multinucleon相互作用的本地费米气体模型完全一致地实现了数据的最佳描述。在最终状态下至少一个质子的情况下，光谱函数模型与数据非常吻合，最值得注意的是，在测量MUON和平面中质子之间的运动学不平衡时，横向到传入的中微子。观察到存在多核互动相互作用的明显指示。还讨论了最终互动的影响。