First measurement of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msub><mml:mover accent="true"><mml:mi>ν</mml:mi><mml:mo stretchy="false">¯</mml:mo></mml:mover><mml:mi>μ</mml:mi></mml:msub></mml:math> and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msub><mml:mi>ν</mml:mi><mml:mi>μ</mml:mi></mml:msub></mml:math> charged-current inclusive interactions on water using a nuclear emulsion detector
A. Hiramoto, Y. Suzuki, A. Ali, S. Aoki, L. Berns, T. Fukuda, Yoko Hanaoka, Y. Hayato, A. K. Ichikawa, H. Kawahara, T. Kikawa, T. Koga, Ryosuke Komatani, M. Komatsu, Y. Kosakai, T. Matsuo, S. Mikado, A. Minamino, Kosuke Mizuno, Yuichi Morimoto, Kunihiro Morishima, N. Naganawa, Mikito Naiki, Mitsuhiro Nakamura, Yuya Nakamura, Nobuaki Nakano, Takayoshi Nakano, T. Nakaya, A. Nishio, T. Odagawa, S. Ogawa, H. Oshima, Hiroki Rokujo, I. Sanjana, Osamu Sato, H. Shibuya, K. Sugimura, L. Suzui, Haruka Takagi, T. Takao, Y. Tanihara, K. Yasutome, M. Yokoyama
Abstract
This paper reports the track multiplicity and kinematics of muons, charged pions, and protons from charged-current inclusive ${\overline{\ensuremath{\nu}}}_{\ensuremath{\mu}}$ and ${\ensuremath{\nu}}_{\ensuremath{\mu}}$ interactions on a water target, measured using a nuclear emulsion detector in the NINJA experiment. A 3-kg water target was exposed to the T2K antineutrino-enhanced beam corresponding to $7.1\ifmmode\times\else\texttimes\fi{}{10}^{20}$ protons on target with a mean energy of 1.3 GeV. Owing to the high granularity of the nuclear emulsion, protons with momenta down to $200\text{ }\text{ }\mathrm{MeV}/c$ from the neutrino-water interactions were detected. We find good agreement between the observed data and model predictions for all kinematic distributions other than the number of charged pions and the muon kinematics shapes. These results demonstrate the capability of measurements with nuclear emulsion to improve neutrino interaction models.