Workpackage 2

T2K detector upgrade and Neutrino Physics

Coordinator: Dr. Emilio Radicioni (INFN)

Task 2.1: Construction and commissioning of the ND280 TPC

The four main areas of activity are the design and production of the field-cages (INFN, IFAE), MM modules and its on-detector electronics (CEA), the mechanical structure interfacing the MM with the field-cages (CEA, NCBJ, IFJ-PAN), and the back-end electronics (CNRS). The conceptual design will be performed by European groups and will be supported by prototyping activities for the field-cages, the resistive MMs and the readout electronics. The tight mechanical requirements for integration of the new detector into the existing experimental layout in J-PARC call for a high level of coordination between the involved European groups and the Japanese partners. After prototyping, the construction will be performed in Europe, where the final detector will be fully assembled and tested, prior to shipping to J-PARC for installation, integration and commissioning.

Task 2.2: Construction and commissioning of the Super FGD

The challenging aspects of this detector are the assembly of the ~ 2 million cubes with their readout fibers, and the integration of MPPCs and front-end electronics in the limited space available between the Super-FGD and the neighboring TPCs. The design and construction will be performed by European and Japanese groups and, as for Task 2.1, requires a close collaboration between the involved partners. Construction will be conducted at CERN, from where the detector will be shipped to J-PARC for installation, integration and commissioning.

Task 2.3: Neutrinos cross section measurement

This task is an excellent playground for a broad community of theoreticians and experimentalists, mixing different skills and backgrounds. It is also a valuable environment for students, where they can enrich the foundations of their career. Cross-section of the different neutrino types on different targets (C, O, Fe) will be published open access and will be accompanied by public data releases in order to allow a broader community to interpret and study them.

Task 2.4: Neutrino oscillation analysis

The first step of the oscillation analysis is the selection of different event samples, each corresponding to a different final state topology and coming with its own efficiency and systematic errors, and it is the result of a coordinated teamwork. The combination of all these samples in a coherent framework requires an even higher level of coordination between different groups. The last step of the oscillation analysis is a simultaneous fit of the different appearance and disappearance samples to extract the oscillation parameters. This is done independently by three different groups, using complementary approaches, both Bayesian and frequentist.