Combined on/off-axis inclusive charged current cross-section measurement on carbon in the T2K near detector complex

The T2K long-baseline neutrino oscillation experiment has a diverse program of neutrino-interaction cross-section measurements using its on-axis and off-axis near detectors. The two near detectors sample different neutrino energy spectra; an analysis using both detectors is able to better probe the energy dependence of few-GeV neutrino interactions than either detector can independently.

This talk describes a simultaneous cross-section measurement on scintillator (CH) target using both near detectors. Neutrino detectors measure total rate, which is a convolution of flux and cross section effects. Because both detectors are exposed to neutrinos from the same beamline, many uncertainties in the neutrino flux prediction will be correlated. This fact combined with the different neutrino energy spectra seen in each detector will improve the sensitivity to the flux and cross-section degeneracy. This analysis will be the first cross-section measurement in T2K to use samples from multiple detectors in the same beamline.