Research Report
ICRR Inter-University Research Program 2021
Research Subject:
Constraining systematics at T2K and SuperKamiokande oscillation analyses
using neutrino-nucleus interaction models
Principal Investigator:
Juan Antonio Caballero Carretero (University of Seville)
Participating Researchers:

Juan Manuel Franco Patiño (University of Seville)

Jesús González Rosa (University of Seville)

Raúl González Jiménez (Complutense University of Madrid)José Manuel Udías Moinelo (Complutense University of Madrid)

Maria Benedetta Barbaro (University of Turin and INFN)

T. William Donnelly (Massachusetts Institute of Technology (MIT))Kimihiro Okumura (University of Tokyo, ICRR)Yoshinari Hayato (University of Tokyo, ICRR)Guillermo D. Megias (University of Tokyo, ICRR & University of Seville)

Summary of Research Result：- Due to the Covid-19 pandemic, the research could not be conducted as
initially planned.
- We will also continue this project on FY2022 under the ICRR Inter-University
Research Program 2022.
In spite of the current situation and travel limitations, the outcomes of theseprojects have been presented at several workshops and conferences as wellas in some proceedings:
T2K Neutrino Interaction Working Group Workshop 2021. Oralcontribution(online).

“MODELLING

SEMI-INCLUSIVE

NEUTRINO-NUCLEUS SCATTERING”. J. M. Franco-Patiño

TNPI2021-XVIII Conference on Theoretical Nuclear Physics in Italy. Oralcontribution (online).

“Semi-inclusive charged-current neutrino-

nucleus reactions: Analysis of Data in the relativistic Plane-Wave
Impulse Approximation”. J.M. Franco Patiño


T2K Cross Section General Workshop 2021. Oral contribution (online).
“Neutrino-nucleus cross sections: Theoretical nuclear models andimplementation in MC event generators” G. D. MegiasProceeding:Semi-inclusivecharged-current

neutrino-nucleus

reactions: analysis of data in the relativistic plane-wave impulse
approximation, J.M. Franco-Patino et al., PoS(NuFact2021) 402, 227(2022). DOI: 10.22323/1.402.0227
Proceeding: Inelastic neutrino-nucleus scattering in the superscaling
model. J.Gonzalez-Rosa, G. D. Megias, J.A. Caballero and G.D. Megias,PoS(NuFact2021) 402, 228 (2022). DOI: 10.22323/1.402.0228

The list of publications related to this project in FY2021 is shown in a
separate document and includes important outcomes published in highimpact factor journals (Nature, Physical Review D, Physical Review C, etc.)
Work is in progress and has been carried out with Prof. Hayato-san (ICRR)
on a joint analysis of low-energy nuclear effects at T2K, Ninja and SK
kinematics in comparison with SuSAv2-MEC and RMF models. Also, incollaboration with Hayato-san, S. Dolan (CERN) and other T2K and SK
researchers, a first implementation of the inclusive and semi-inclusive RMF1p1h models in NEUT is expected in the next months. Some successfulcomparisons of the RMF models (using different choices for the nuclear
potentials) with T2K semi-inclusive and TKI measurements has been recently
performed and a manuscript is now in preparation. All this will allow thereweight of several parameters for the oscillation analysis, the study of
nuclear-medium

effects,andacomparison

between

nuclear

opticalpotentials and cascade models in generators, among other issues. Moreover,
we have also started a collaboration with Prof. Sato-san (Osaka University)and Prof. Hayato-san to implement the DCC model from the Osaka group,
which describes nucleonic resonances, in the SuSAv2 framework and tocompare this implementation with the one being developed in NEUT. The
outcomes of these research lines will be published in coming months.
With regard to the ICRR Research Program, the Univesity of Seville group (J.
A. Caballero, G. D. Megias and others) has obtained a 3-year R&D project of
the Spanish Ministry of Science in which Prof. Hayato-san (ICRR) has been
included as collaborator. The University of Seville consider this collaborationa research line of strategic interest and has recently approved two specialallocations, in 2021 and 2022, to support the participation of theirresearchers in the T2K Collaboration, which have allowed the University of
Seville to officially join T2K as a member institution.
No.