Neutrino event detection with nuclear emulsion in the NINJA experiment

It is essential for the T2K experiment to measure low momentum protons and understand multi-nucleon interactions in the sub-multi GeV region in order to reduce systematic uncertainty. The NINJA experiment aims to measure neutrino-nucleus interactions on a water target precisely using nuclear emulsion. Since nuclear emulsion has sub-micron position resolution, it allows us to observe the interaction vertex clearly. Therefor, the emulsion detector is expected to provide far more precise information on short-track particles that are hard to reconstruct in the current T2K detectors. We have carried out several detector test run at J-PARC so far. In the latest run, started in Oct 2017, we placed a water target emulsion detector (ECC) in front of the T2K on-axis near detector INGRID. A newly-constructed scintillating fiber tracker placed between ECC and INGRID enables a hybrid analysis using both detectors. We will present the detector performance and analysis status for the latest run.