Precise measurement of neutrino–nucleus interactions with an accelerator neutrino beam is highly important for current and future neutrino oscillation experiments. To measure muon-neutrino ...charged-current interactions with nuclear-emulsion-based hybrid detector, muon track matching among the detectors are essential. We describe the design and performance of a newly developed scintillation tracker for the muon track matching in the neutrino–nucleus interaction measurement with nuclear emulsion detectors. The muon tracks are reconstructed using the scintillation tracker and another detector called Baby MIND, then, they are matched with the tracks in nuclear emulsion detectors.
The scintillation tracker consists of four layers of horizontally and vertically aligned scintillator bars, covering an area of 1m×1m. In the layer, 24mm-wide plastic scintillator bars are specially arranged with deliberate gaps between each other. By recognizing the hit pattern of the four layers, a precise positional resolution of 2.5mm is achieved while keeping the number of readout channels as small as 256. The efficiency of the track matching is evaluated to be more than 97% for forward-going muons, and the positional and angular resolutions of the scintillation tracker are 2.5mm and 20–40mrad respectively. The results demonstrate the usefulness of the design of the scintillation tracker for the muon track matching in the nuclear-emulsion-based neutrino–nucleus interaction measurements.
This paper reports the track multiplicity and kinematics of muons, charged pions, and protons from charged-current inclusive νμ and νμ 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 × 1020 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 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.
Background
Perflubutane microbubbles, a second‐generation ultrasound contrast agent, are phagocytized by Kupffer cells. This characteristic may be useful to differentiate diffuse hepatic diseases in ...dogs.
Hypothesis/objectives
To determine whether the washout ratio in the hepatic vein (HV) measured by contrast‐enhanced ultrasonography (CEUS) can distinguish between inflammatory and noninflammatory hepatic disorders in dogs.
Animals
Forty‐one client‐owned dogs with hepatic disorders including 14 with hepatitis, 7 with primary hypoplasia of the portal vein (PHPV), 9 with congenital portosystemic shunt (cPSS), and 11 with other hepatopathy were enrolled. Six dogs without hepatic disease also were evaluated as healthy controls.
Methods
Dogs with hepatic disorders were prospectively included. Contrast‐enhanced ultrasonography of the HV was performed for 2 minutes. Washout ratio was defined as the attenuation rate from peak intensity to the intensity at the end of the CEUS study.
Results
Washout ratio in the hepatitis group (median, 18.0%; range, 2.0–37.0%) was significantly lower than that of the PHPV (median, 52.2%; range, 11.5–86.3%), cPSS (median, 60.0%; range, 28.6–77.4%), other hepatopathy (median, 70.5%; range, 26.6–88.4%), and normal (median, 78.0%; range, 60.7–91.7%) groups. The area under the receiver operating characteristic curve for hepatitis was 0.960, with a 95% confidence interval (CI) of 0.853–0.990. Washout ratio ≤37.1% resulted in a sensitivity of 100% (95% CI, 78.5–100%) and specificity of 85.2% (95% CI, 67.5–94.1%) for the prediction of hepatitis.
Conclusions and Clinical Importance
Washout ratio can distinguish hepatitis from the other noninflammatory disorders with high accuracy. This result might reflect impaired Kupffer cell phagocytosis in dogs with hepatitis.
Abstract
Precise neutrino–nucleus interaction measurements in the sub-multi-GeV region are important to reduce the systematic uncertainty in future neutrino oscillation experiments. Furthermore, an ...excess of
${\nu_e}$
interactions, as a possible interpretation of the existence of a sterile neutrino, has been observed in such an energy region. The nuclear emulsion technique can measure all the final state particles with low energy threshold for a variety of targets (Fe, C, H
${_2}$
O, and so on). Its sub-
$\mu$
m position resolution allows measurements of the
${\nu_e}$
cross-section with good electron/gamma separation capability. We started a new experiment at J-PARC to study sub-multi-GeV neutrino interactions by introducing the nuclear emulsion technique. The J-PARC T60 experiment has been implemented as a first step in such a project. Systematic neutrino event analysis with full scanning data in the nuclear emulsion detector was performed for the first time. The first neutrino event detection and its analysis are described in this paper.
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 a 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 reproduced well by current neutrino interaction models. These results demonstrate the capability of the detector in the detailed measurement of neutrino–nucleus interactions around the 1 GeV energy region.
Abstract
We describe the first ever implementation of a clock-based, multi-stage emulsion shifter in an accelerator neutrino experiment. The system was installed in the neutrino monitoring building ...at the Japan Proton Accelerator Research Complex as part of a test experiment, T60, and stable operation was maintained for a total of 126.6 days. By applying time information to emulsion films, various results were obtained. Time resolutions of 5.3–14.7 s were evaluated in an operation spanning 46.9 days (yielding division numbers of 1.4–3.8
$\times10^{5}$
). By using timing and spatial information, reconstruction of coincident events consisting of high-multiplicity and vertex-contained events, including neutrino events, was performed. Emulsion events were matched to events observed by INGRID, one of the on-axis near detectors of the T2K experiment, with high reliability (98.5%), and hybrid analysis of the emulsion and INGRID events was established by means of the multi-stage shifter. The results demonstrate that the multi-stage shifter can feasibly be used in neutrino experiments.
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