The work performed during the project has addressed the following topics:
- Using relativistic mean field (RMF) and superscaling (SuSAv2) models, several T2K and SK data have been studied with the aim of analyzing low-energy nuclear effects and improve data analysis. Unlike other models, we have found important differences between carbon and oxygen at these kinematics, in accordance with some T2K data.
- The RMF and SuSAv2 codes has been adapted and optimized to implement them in the NEUT event generator. After the full implementation, the RMF and SuSAv2 models will be used directly for the oscillation analysis and the determination of oscillation parameters.
The project has been carried out in collaboration with ICRR, T2K and SK members: S. Dolan, Y. Hayato and others; and also with researchers from the University of Seville, Turin, Granada and Complutense of Madrid. Guillermo D. Megias has got involved in regular bi-weekly meetings with different T2K working groups: NIWG (Neutrino Interaction Working Group) and XSEC WG (Cross Section Working Group), where details of the project have been regularly discussed.
Within this project we have obtained the most accurate comparison with T2K neutrino cross-section measurements, showing a large improvement with regards to other models. We have also extended the SuSAv2 and RMF models to analyze neutrino reactions on argon, an asymmetric nucleus, observing a good agreement with recent semi-inclusive measurements.
Guillermo D. Megias has also taken shifts on the T2K and SK facilities. These shifts are focused on real-time diagnosis and basic trouble-shooting of the beam operation, data acquisition or detector activity. Guillermo Megias has also supervised and trained other new members of the collaboration.
A collaboration has been established with the NINJA group, a Japanese collaboration aimed to measure neutrino-water interactions using a nuclear emulsion detector. We have developed a semi-phenomenological model to analyze the resonance region in neutrino-nucleus reactions and in collaboration with the ICRR and the Univ. of Osaka we are adding high-energy nucleonic resonances in our models. Another collaboration with MIT and FermiLab has allowed to implement our models in their generators and to analyze electron scattering data which provide essential information for neutrino oscillation experiments. This collaboration has led to a publication in Nature.
This project has led to more than 20 publications (Nature, Phys. Rev. D, Astroph. Journal, PTEP, etc.), several contributions to international conferences and workshops (NEUTRINO2020, NuFact21, European Researcher’s Night 2020, etc.) and several media interviews.
