First measurement of the charged current νμ double differential cross section on a water target without pions in the final state

This paper reports the first differential measurement of the charged-current νμ interaction cross section on water with no pions in the final state. The unfolded flux-averaged measurement using the T2K off-axis near detector is given in double-differential bins of μ+ momentum and angle. The integrated cross section in a restricted phase space is σ = ( 1.11 ± 0.18 ) × 10−38 cm2 per water molecule. Comparisons with several nuclear models are also presented.