Measurements of the νμ\nu_{\mu} and νˉμ\bar{\nu}_{\mu}-induced Coherent Charged Pion Production Cross Sections on 12C^{12}C by the T2K experiment

We report an updated measurement of the $\nu_{\mu}$-induced, and the first measurement of the $\bar{\nu}_{\mu}$-induced coherent charged pion production cross section on $^{12}C$ nuclei in the T2K experiment. This is measured in a restricted region of the final-state phase space for which $p_{\mu,\pi} > 0.2$ GeV, $\cos(\theta_{\mu}) > 0.8$ and $\cos(\theta_{\pi}) > 0.6$, and at a mean (anti)neutrino energy of 0.85 GeV using the T2K near detector. The measured $\nu_{\mu}$ CC coherent pion production flux-averaged cross section on $^{12}C$ is $(2.98 \pm 0.37 (stat.) \pm 0.31 (syst.) \substack{ +0.49 \\ -0.00 } \mathrm{ (Q^2\,model)}) \times 10^{-40}~\mathrm{cm}^{2}$. The new measurement of the $\bar{\nu}_{\mu}$-induced cross section on $^{12}{C}$ is $(3.05 \pm 0.71 (stat.) \pm 0.39 (syst.) \substack{ +0.74 \\ -0.00 } \mathrm{(Q^2\,model)}) \times 10^{-40}~\mathrm{cm}^{2}$. The results are compatible with both the NEUT 5.4.0 Berger-Sehgal (2009) and GENIE 2.8.0 Rein-Sehgal (2007) model predictions

Measurements of the νμ and ν¯μ -induced coherent charged pion production cross sections on C12 by the T2K experiment

We report an updated measurement of the ν μ -induced, and the first measurement of the ¯ ν μ -induced coherent charged pion production cross section on 12 C nuclei in the Tokai-to-Kamioka experiment. This is measured in a restricted region of the final-state phase space for which p μ , π > 0.2     GeV , cos ( θ μ ) > 0.8 and cos ( θ π ) > 0.6 , and at a mean (anti)neutrino energy of 0.85 GeV using the T2K near detector. The measured ν μ charged current coherent pion production flux-averaged cross section on 12 C is ( 2.98 ± 0.37 ( stat ) ± 0.31 ( syst ) + 0.49 − 0.00 ( Q 2   model ) ) × 10 − 40     cm 2 . The new measurement of the ¯ ν μ -induced cross section on 12 C is ( 3.05 ± 0.71 ( stat ) ± 0.39 ( syst ) + 0.74 − 0.00 ( Q 2   model ) ) × 10 − 40     cm 2 . The results are compatible with both the NEUT 5.4.0 Berger-Sehgal (2009) and GENIE 2.8.0 Rein-Sehgal (2007) model predictions

Scintillator ageing of the T2K near detectors from 2010 to 2021

The T2K experiment widely uses plastic scintillator as a target for neutrino interactions and an active medium for the measurement of charged particles produced in neutrino interactions at its near detector complex. Over 10 years of operation the measured light yield recorded by the scintillator based subsystems has been observed to degrade by 0.9–2.2% per year. Extrapolation of the degradation rate through to 2040 indicates the recorded light yield should remain above the lower threshold used by the current reconstruction algorithms for all subsystems. This will allow the near detectors to continue contributing to important physics measurements during the T2K-II and Hyper-Kamiokande eras. Additionally, work to disentangle the degradation of the plastic scintillator and wavelength shifting fibres shows that the reduction in light yield can be attributed to the ageing of the plastic scintillator. The long component of the attenuation length of the wavelength shifting fibres was observed to degrade by 1.3–5.4% per year, while the short component of the attenuation length did not show any conclusive degradation

Cooperative action of germ-line mutations in decorin and p53 accelerates lymphoma tumorigenesis

Ectopic expression of decorin in a wide variety of transformed cells results in growth arrest and the inability to generate tumors in nude mice. This process is caused by a decorin-mediated activation of the epidermal growth factor receptor, which leads to a sustained induction of endogenous p21(WAF1/CIP1) (the cyclin-dependent kinase inhibitor p21) and growth arrest. However, mice harboring a targeted disruption of the decorin gene do not develop spontaneous tumors. To test the role of decorin in tumorigenesis, we generated mice lacking both decorin and p53, an established tumor-suppressor gene. Mice lacking both genes showed a faster rate of tumor development and succumbed almost uniformly to thymic lymphomas within 6 months [mean survival age (T(50)) ∼4 months]. Mice harboring one decorin allele and no p53 gene developed the same spectrum of tumors as the double knockout animals, but had a survival rate similar to the p53 null animals (T(50) ∼ 6 months). Ectopic expression of decorin in thymic lymphoma cells isolated from double mutant animals markedly suppressed their colony-forming ability. When these lymphoma cells were cocultured with fibroblasts derived from either wild-type or decorin null embryos, the cells grew faster in the absence of decorin. Moreover, exogenous decorin proteoglycan or its protein core significantly retarded their growth in vitro. These results indicate that the lack of decorin is permissive for lymphoma tumorigenesis in a mouse model predisposed to cancer and suggest that germ-line mutations in decorin and p53 may cooperate in the transformation of lymphocytes and ultimately lead to a more aggressive phenotype by shortening the tumor latency

Parametrized uncertainties in the spectral function model of neutrino charged-current quasielastic interactions for oscillation analyses

A substantial fraction of systematic uncertainties in neutrino oscillation experiments stem from the lack of precision in modeling the nuclear target in neutrino-nucleus interactions. Whilst this has driven significant progress in the development of improved nuclear models for neutrino scattering, it is crucial that the models used in neutrino data analyses be accompanied by parameters and associated uncertainties that allow the coverage of plausible nuclear physics. Based on constraints from electron scattering data, we propose such a set of parameters, which can be applied to nuclear shell models, and test their application to the Benhar et al. [Nucl. Phys. A579, 493 (1994)] spectral function model. The parametrization is validated through a series of maximum likelihood fits to cross section measurements made by the T2K and MINERvA experiments, which also permit an exploration of the power of near-detector data to provide constraints on the parameters in neutrino oscillation analyses.Agence Nationale de la Recherche (ANR), France ANR-10-LABX-0038, ANR-11-IDEX0003-01Centro Nacional de Ciencias, Polonia UMO-2018/ 30/E/ST2/00441Centre national de la recherche scientifique (CNRS), France IN2P3Programa de Investigación Interuniversitaria ICRR, Universidad de Tokio, Japón FY2023European Commission (EC). Fondo Europeo de Desarrollo Regional (FEDER) PID2020–114687GB-100Junta de Andalucía, España, FQM160Ministry of Science and Higher Education. Poland 2023/WK/0

Parametrized uncertainties in the spectral function model of neutrino charged-current quasielastic interactions for oscillation analyses

International audienceA substantial fraction of systematic uncertainties in neutrino oscillation experiments stem from the lack of precision in modeling the nuclear target in neutrino-nucleus interactions. Whilst this has driven significant progress in the development of improved nuclear models for neutrino scattering, it is crucial that the models used in neutrino data analyses be accompanied by parameters and associated uncertainties that allow the coverage of plausible nuclear physics. Based on constraints from electron scattering data, we develop such a set of parameters, which can be applied to nuclear shell models, and test their application to the Benhar et al spectral function model. The parametrization is validated through a series of maximum likelihood fits to cross-section measurements made by the T2K and MINERvA experiments, which also permit an exploration of the power of near-detector data to provide constraints on the parameters in neutrino oscillation analyses

Parametrized uncertainties in the spectral function model of neutrino charged-current quasielastic interactions for oscillation analyses

A substantial fraction of systematic uncertainties in neutrino oscillation experiments stem from the lack of precision in modeling the nuclear target in neutrino-nucleus interactions. Whilst this has driven significant progress in the development of improved nuclear models for neutrino scattering, it is crucial that the models used in neutrino data analyses be accompanied by parameters and associated uncertainties that allow the coverage of plausible nuclear physics. Based on constraints from electron scattering data, we develop such a set of parameters, which can be applied to nuclear shell models, and test their application to the Benhar et al spectral function model. The parametrization is validated through a series of maximum likelihood fits to cross-section measurements made by the T2K and MINERvA experiments, which also permit an exploration of the power of near-detector data to provide constraints on the parameters in neutrino oscillation analyses

Parametrized uncertainties in the spectral function model of neutrino charged-current quasielastic interactions for oscillation analyses

International audienceA substantial fraction of systematic uncertainties in neutrino oscillation experiments stem from the lack of precision in modeling the nuclear target in neutrino-nucleus interactions. Whilst this has driven significant progress in the development of improved nuclear models for neutrino scattering, it is crucial that the models used in neutrino data analyses be accompanied by parameters and associated uncertainties that allow the coverage of plausible nuclear physics. Based on constraints from electron scattering data, we develop such a set of parameters, which can be applied to nuclear shell models, and test their application to the Benhar et al spectral function model. The parametrization is validated through a series of maximum likelihood fits to cross-section measurements made by the T2K and MINERvA experiments, which also permit an exploration of the power of near-detector data to provide constraints on the parameters in neutrino oscillation analyses