Measurements of the reactions 12C(νμ,μ−)12Ng.s. and 12C(νμ,μ−)X

Charged current scattering of νμ on 12C has been studied [1] using a π+ decay-in-flight νμ beam at the Los Alamos Meson Physics Facility. The observed flux-averaged cross section for the exclusive reaction 12C(νμ,μ−)12Ng.s. of (6.6±1.0±1.0)×10−41 cm2 agrees well with reliable theoretical expectations. A measurement was also obtained for the inclusive cross section to all accessible 12N states, 12C(νμ,μ−)X. This flux-averaged cross section is (11.2±0.3±1.8)×10−40 cm2, which is approximately half of that given by a recent Continuum Random Phase Approximation (CRPA) calculation [2], but is in agreement with other calculations [3].