Muon-neutrino carbon charged-current interaction near the muon threshold

A measurement of the muon-neutrino carbon charged-current cross section, {sup 12}C({nu}{sub {mu}},{mu}{sup {minus}}){ital X}, was performed using the in-flight pion-decay neutrino source at the LAMPF accelerator. At an average interacting neutrino energy of 202 MeV an inclusive cross section of (15.9{plus minus}2.6{plus minus}3.7){times}10{sup {minus}39} cm{sup 2} was measured. This value is in best agreement with the Fermi-gas model and is in disagreement with a previous experiment and subsequent calculations that yielded substantially lower cross sections. However, the muon energy spectrum shows a marked depletion of events at high energies compared to the Fermi-gas model. From a small sample of events in which the final-state nucleus was in the ground state of {sup 12}N, a cross section for the reaction {sup 12}C({nu}{sub {mu}},{mu}{sup {minus}}){sup 12}N(g.s.) of (1.7{plus minus}0.8{plus minus}0.3){times}10{sup {minus}39} cm{sup 2} or about 11{plus minus}5 % of the total event rate was obtained.