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

Sensitivity of the upgraded T2K Near Detector to constrain neutrino and antineutrino interactions with no mesons in the final state by exploiting nucleon-lepton correlations

International audienceThe most challenging and impactful uncertainties that future accelerator-based measurements of neutrino oscillations must overcome stem from our limited ability to model few-GeV neutrino-nucleus interactions. In particular, it is crucial to better understand the nuclear effects which can alter the final state topology and kinematics of neutrino interactions, inducing possible biases in neutrino energy reconstruction. The upgraded ND280 near detector of the T2K experiment will directly confront neutrino interaction uncertainties using a new suite of detectors with full polar angle acceptance, improved spatial resolutions, neutron detection capabilities and reduced tracking thresholds. In this manuscript we explore the physics sensitivity that can be expected from the upgraded detector, specifically focusing on the additional sensitivity to nuclear effects and how they can be constrained with future measurements of kinematic variables constructed using both outgoing lepton and nucleon kinematics

Malaysian Chinese speakers' attitudes towards Foochow, Hokkien and Mandarin

The study examines the influence of gender, age and socio-economic status on attitudes of Foochow and Hokkien towards their ethnic language and Mandarin. The matched guise test results of 120 Foochow and 120 Hokkien participants in Kuching, Malaysia, showed positive attitudes towards Mandarin on all the 15 traits. The Hokkien participants were more positive than the Foochow participants towards speakers of their own ethnic language. Foochow speakers were perceived as loud, and the male Foochow speaker was rated unfavourably on five other traits. Multivariate analysis of variance results showed that gender significantly influenced the Foochow participants' ratings of the wealth of Foochow speakers and the Hokkien participants' ratings of the easy-going nature of Mandarin speakers, the gentleness and solidarity of the male Mandarin speaker, and the height and intelligence of the male Hokkien speaker. Age influenced the attributions of status to the female Foochow speaker and solidarity with the female Mandarin speaker. Socio-economic status influenced the ratings of the most number of traits. Interaction effects were also found. The underlying dimensions loaded onto one factor each for Foochow (easy-going and rich) and Hokkien (formal, strong solidarity) and two different factors for Mandarin, suggesting different stereotypes of dialect and Mandarin speakers

Measurements of the νμ and ν ¯ μ -induced coherent charged pion production cross sections on C 12 by the T2K experiment

We report an updated measurement of the νμ-induced, and the first measurement of the ν¯μ-induced coherent charged pion production cross section on C12 nuclei in the Tokai-to-Kamioka experiment. This is measured in a restricted region of the final-state phase space for which pμ,π&gt;0.2 GeV, cos(θμ)&gt;0.8 and cos(θπ)&gt;0.6, and at a mean (anti)neutrino energy of 0.85 GeV using the T2K near detector. The measured νμ charged current coherent pion production flux-averaged cross section on C12 is (2.98±0.37(stat)±0.31(syst)-0.00+0.49(Q2 model))×10-40 cm2. The new measurement of the ν¯μ-induced cross section on C12 is (3.05±0.71(stat)±0.39(syst)-0.00+0.74(Q2 model))×10-40 cm2. The results are compatible with both the NEUT 5.4.0 Berger-Sehgal (2009) and GENIE 2.8.0 Rein-Sehgal (2007) model predictions.</p