Measurement of the $\nu_\mu$ CCQE cross section on carbon with the ND280 detector at T2K

TL;DR

This paper presents a measurement of the muon neutrino charged-current quasi-elastic cross section on carbon at around 1 GeV using the T2K ND280 detector, providing data crucial for neutrino oscillation studies.

Contribution

It reports the first measurement of the CCQE cross section on carbon at T2K, including flux-integrated values and the axial mass parameter, with detailed energy dependence analysis.

Findings

Flux-integrated CCQE cross section: (0.83 ± 0.12) × 10^{-38} cm^2

Effective axial mass M_A^{QE}: 1.26^{+0.21}_{-0.18} GeV/c^2

Good agreement with NEUT MC prediction

Abstract

The Charged-Current Quasi-Elastic (CCQE) interaction, $\nu_{l} + n \rightarrow l^{-} + p$, is the dominant CC process at $E_\nu \sim 1$ GeV and contributes to the signal in accelerator-based long-baseline neutrino oscillation experiments operating at intermediate neutrino energies. This paper reports a measurement by the T2K experiment of the $\nu_{\mu}$ CCQE cross section on a carbon target with the off-axis detector based on the observed distribution of muon momentum ($p_\mu$) and angle with respect to the incident neutrino beam ($\theta_\mu$). The flux-integrated CCQE cross section was measured to be $(0.83 \pm 0.12) \times 10^{-38}\textrm{ cm}^{2}$ in good agreement with NEUT MC value of ${0.88 \times 10^{-38}} \textrm{ cm}^{2}$. The energy dependence of the CCQE cross section is also reported. The axial mass, $M_A^{QE}$, 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) $p_{\mu}cos\theta_\mu$ distribution, the effective $M_A^{QE}$ parameter was measured to be ${1.26^{+0.21}_{-0.18} \textrm{ GeV}/c^{2}}$ (${1.43^{+0.28}_{-0.22} \textrm{ GeV}/c^{2}}$).