First measurement using a nuclear emulsion detector of the $\nu_{\mu}$ charged-current cross section on iron around the 1$\,$GeV energy region

TL;DR

This study used a nuclear emulsion detector to precisely measure the muon neutrino charged-current cross section on iron at around 1.5 GeV, confirming model predictions and demonstrating the detector's effectiveness for detailed neutrino interaction studies.

Contribution

First measurement of the muon neutrino charged-current cross section on iron using a nuclear emulsion detector at around 1.5 GeV energy.

Findings

Measured cross section: (1.28 ± 0.11(stat.)+0.12−0.11(syst.)) × 10^{-38} cm^2/nucleon.

Cross section in limited phase space: (0.84 ± 0.07(stat.)+0.07−0.06(syst.)) × 10^{-38} cm^2/nucleon.

Results agree with previous measurements and current neutrino interaction models.

Abstract

We have carried out $\nu_{\mu}$ charged-current interaction measurement on iron using an emulsion detector exposed to the T2K neutrino beam in the J-PARC neutrino facility. The data samples correspond to 4.0$\times$10$^{19}$ protons on target, and the neutrino mean energy is 1.49$\,$GeV. The emulsion detector is suitable for precision measurements of charged particles produced in neutrino-iron interactions with a low momentum threshold thanks to thin-layered structure and sub-$\mu$m spatial resolution. The charged particles are successfully detected, and their multiplicities are measured using the emulsion detector. The cross section was measured to be $\sigma^{\mathrm{Fe}}_{\mathrm{CC}} = (1.28 \pm 0.11({\mathrm{stat.}})^{+0.12}_{-0.11}({\mathrm{syst.}})) \times 10^{-38} \, {\mathrm{cm}}^{2}/{\mathrm{nucleon}}$. The cross section in a limited kinematic phase space of induced muons, $\theta_{\mu} < 45^{\circ}$ and $p_{\mu} > 400 \, {\rm MeV}/c$, on iron was $\sigma^{\mathrm{Fe}}_{\mathrm{CC \hspace{1mm} phase \hspace{0.5mm} space}} = (0.84 \pm 0.07({\mathrm{stat.}})^{+0.07}_{-0.06}({\mathrm{syst.}})) \times 10^{-38} \, {\mathrm{cm}}^{2}/{\mathrm{nucleon}}$. The cross-section results are consistent with previous values obtained via different techniques using the same beamline, and they are well reproduced by current neutrino interaction models. These results demonstrate the capability of the detector towards the detailed measurements of the neutrino-nucleus interactions around the 1$\,$GeV energy region.