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Abstract:

This paper reports a measurement by the T2K experiment of the ν μ charged current quasielastic (CCQE) cross section on a carbon target with the off-axis detector based on the observed distribution of muon momentum ( p μ ) and angle with respect to the incident neutrino beam ( θ μ ). The flux-integrated CCQE cross section was measured to be ⟨ σ ⟩ = ( 0.83 ± 0.12 ) × 10 − 38     cm 2 . The energy dependence of the CCQE cross section is also reported. The axial mass, M QE A , of the dipole axial form factor was extracted assuming the Smith-Moniz CCQE model with a relativistic Fermi gas nuclear model. Using the absolute (shape-only) p μ − cos θ μ distribution, the effective M QE A parameter was measured to be 1.2 6 + 0.21 − 0.18     GeV / c 2 ( 1.4 3 + 0.28 − 0.22     GeV / c 2 ).

Abstract:

This paper describes the hardware and operations of the Neutrinos at the Main Injector (NuMI) beam at Fermilab. It elaborates on the design considerations for the beam as a whole and for individual elements. The most important design details of individual components are described. Beam monitoring systems and procedures, including the tuning and alignment of the beam and NuMI long-term performance, are also discussed.