Measurement of neutrino-nucleus interactions with the upgraded ND280 detector at T2K

东海到神冈，T2K，是一个以研究中微子振荡为主要目标的长基线实验。这项实验使用了J-PARC设施产生的Muon中微子(或反中微子)光束，目标是超级神冈(Super-K)，该光束位于光束下游295公里处，离轴角度为2.5度。该实验还使用了ND280离轴近探测器，通过与远探测器Super-K一起工作，可以测量振荡前后束流中的电子和Muon中微子。ND280近探测器的主要目标是测量和约束中微子通量和测量相互作用截面。这些测量被用来估计在Super-K观测到的中微子相互作用的种类，减少了测量中的系统不确定性。不同事件的分类依赖于使用精确的颗粒识别(PID)，利用ND280子探测器收集的数据来正确识别每个事件。在振动分析中，主要的系统不确定性是横截面不确定性。然而，ND280 NEAR探测器目前正在进行重大升级，拆除了其中一个旧探测器，并在其位置安装了所有新的子探测器。这些新的探测器应该会显著提高ND280的性能和灵敏度。然后，可以利用升级后的ND280 NEAR探测器记录的新数据来创建改进的PID，以改进事件分类并减少测量的系统不确定性。升级后的ND280的改进的PID将用于测量中微子截面。

Tokai-to-Kamioka, T2K, is a long baseline experiment with the primary goal of investigating neutrino oscillations. This experiment uses a muon neutrino (or antineutrino) beam, produced at the J-PARC facility, targeting Super-Kamiokande (Super-K) which is positioned 295 km downstream of the beam at an off-axis angle of 2.5 degrees. The experiment also uses the ND280 off-axis near detector and by working in conjunction with the far detector, Super-K, measurements of the electron and muon neutrinos present in the beam before and after oscillation can be taken.The ND280 near detector has the primary goal of measuring, and constraining, the neutrino flux and measuring the interaction cross sections. These measurements are used to estimate the varieties of neutrino interactions that would be observed at Super-K, reducing the systematic uncertainty in the measurements. Classification of the different events relies on the use of an accurate particle identification (PID), utilising the data collected by the ND280 sub-detectors to correctly identify each event. The dominant systematic uncertainty in the oscillation analysis is the cross-section uncertainty. However, the ND280 near detector is currently undergoing a major upgrade, removing one of the old detectors and installing all new sub-detectors in its place. These new detectors should significantly improve the performance and sensitivity of ND280. The new data that will be recorded by the upgraded ND280 near detector can then be exploited as to create an improved PID to improve event classification and reduce the systematic uncertainties of the measurements. The improved PID of the upgraded ND280 will be used to take measurements of the neutrino cross-section.