M. Ishitsuka
A5111488722- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Particle Detector Development and Performance
- Quantum Chromodynamics and Particle Interactions
- Neutrino Physics Research
- Astrophysics and Cosmic Phenomena
- Dark Matter and Cosmic Phenomena
- Computational Physics and Python Applications
- Radiation Detection and Scintillator Technologies
- Cosmology and Gravitation Theories
- Atomic and Subatomic Physics Research
- Nuclear Physics and Applications
- Particle accelerators and beam dynamics
- Gamma-ray bursts and supernovae
- Superconducting Materials and Applications
- Distributed and Parallel Computing Systems
- Muon and positron interactions and applications
- Medical Imaging Techniques and Applications
- Black Holes and Theoretical Physics
- Nuclear reactor physics and engineering
- Atmospheric Ozone and Climate
- Structural Analysis of Composite Materials
- Noncommutative and Quantum Gravity Theories
- Advanced Data Storage Technologies
- Solar and Space Plasma Dynamics
Tokyo University of Science
2017-2024
The University of Tokyo
2005-2024
Kavli Institute for the Physics and Mathematics of the Universe
2024
Tokyo Institute of Technology
2014-2023
University of Bern
2023
Albert Einstein College of Medicine
2023
Eötvös Loránd University
2023
Boston University
2023
Duke University
2023
Universidad Autónoma de Madrid
2023
The Double Chooz experiment presents an indication of reactor electron antineutrino disappearance consistent with neutrino oscillations. An observed-to-predicted ratio events 0.944±0.016(stat)±0.040(syst) was obtained in 101 days running at the nuclear power plant France, two 4.25 GW(th) reactors. results were from a single 10 m(3) fiducial volume detector located 1050 m cores. flux prediction used Bugey4 measurement after correction for differences core composition. deficit can be...
Solar neutrino measurements from 1258 days of data the Super-Kamiokande detector are presented. The based on recoil electrons in energy range 5.0--20.0 MeV. measured solar flux is $2.32\ifmmode\pm\else\textpm\fi{}0.03(\mathrm{stat}{)}_{\ensuremath{-}0.07}^{+0.08}(\mathrm{syst})\ifmmode\times\else\texttimes\fi{}{10}^{6}{\mathrm{cm}}^{\ensuremath{-}2}{\mathrm{s}}^{\ensuremath{-}1}$, which $45.1\ifmmode\pm\else\textpm\fi{}0.5(\mathrm{stat}{)}_{\ensuremath{-}1.4}^{+1.6}(\mathrm{syst})%$ that...
The K2K experiment observes indications of neutrino oscillation: a reduction $\nu_\mu$ flux together with distortion the energy spectrum. Fifty-six beam events are observed in Super-Kamiokande (SK), 250 km from production point, an expectation $80.1^{+6.2}_{-5.4}$. Twenty-nine one ring $\mu$-like used to reconstruct spectrum, which is better matched expected spectrum oscillation than without. probability that at SK explained by statistical fluctuation without less 1%.
We present a combined analysis of fully-contained, partially-contained and upward-going muon atmospheric neutrino data from 1489 d exposure the Super-Kamiokande detector. The samples span roughly five decades in energy, 100 MeV to 10 TeV. A detailed Monte Carlo comparison is described presented. fit expectation, found be consistent with oscillations ${\ensuremath{\nu}}_{\ensuremath{\mu}}\ensuremath{\leftrightarrow}{\ensuremath{\nu}}_{\ensuremath{\tau}}$ ${sin}^{2}2\ensuremath{\theta}>0.92$...
The previously published atmospheric neutrino data did not distinguish whether muon neutrinos were oscillating into tau or sterile neutrinos, as both hypotheses fit the data. Using recorded in 1100 live days of Super-Kamiokande detector, we use three complementary samples to study difference zenith angle distribution due neutral currents and matter effects. We find no evidence favoring reject hypothesis at 99% confidence level. On other hand, that oscillation between suffices explain all...
We report the result of a search for neutrino oscillations using precise measurements recoil electron energy spectrum and zenith angle variations solar flux from 1258 days neutrino-electron scattering data in Super-Kamiokande. The absence significant variation distortion places strong constraints on mixing mass difference flux-independent way. Using Super-Kamiokande measurement addition, two allowed regions at large are found.Received 19 March...
We present results for ${\ensuremath{\nu}}_{\ensuremath{\mu}}$ oscillation in the KEK to Kamioka (K2K) long-baseline neutrino experiment. K2K uses an accelerator-produced beam with a mean energy of 1.3 GeV directed at Super-Kamiokande detector. observed energy-dependent disappearance ${\ensuremath{\nu}}_{\ensuremath{\mu}}$, which we presume have oscillated ${\ensuremath{\nu}}_{\ensuremath{\tau}}$. The probability that would observe these if there is no 0.0050% ($4.0\ensuremath{\sigma}$).
The details of Super-Kamiokande-I’s solar neutrino analysis are given. Solar measurement in Super-Kamiokande is a high statistics collection 8B neutrinos via neutrino-electron scattering. method and results the 1496 day data sample presented. final oscillation for presented also.50 MoreReceived 30 August 2005DOI:https://doi.org/10.1103/PhysRevD.73.112001©2006 American Physical Society
The results of the second phase Super-Kamiokande solar neutrino measurement are presented and compared to first phase. flux spectrum time variation as well oscillation statistically consistent with do not show spectral distortion. time-dependent combined phases coincides full period cycle 23 shows no correlation activity. measured $^{8}\mathrm{B}$ total is...
The Double Chooz experiment has observed 8249 candidate electron antineutrino events in 227.93 live days with 33.71 GW-ton-years ($\mathrm{\text{reactor power}}\ifmmode\times\else\texttimes\fi{}\mathrm{\text{detector mass}}\ifmmode\times\else\texttimes\fi{}\mathrm{\text{live time}}$) exposure using a $10.3\text{ }\text{ }{\mathrm{m}}^{3}$ fiducial volume detector located at 1050 m from the reactor cores of nuclear power plant France. expectation case ${\ensuremath{\theta}}_{13}=0$ is 8937...
This Letter reports new results from the MINOS experiment based on a two-year exposure to muon neutrinos Fermilab NuMI beam. Our data are consistent with quantum-mechanical oscillations of neutrino flavor mass splitting |Deltam2| = (2.43+/-0.13) x 10(-3) eV2 (68% C.L.) and mixing angle sin2(2theta) > 0.90 (90% C.L.). disfavor two alternative explanations for disappearance in flight: namely, decays into lighter particles quantum decoherence neutrinos, at 3.7 5.7 standard-deviation levels,...
We report results from the first search for νμ→νe transitions by NOvA experiment. In an exposure equivalent to 2.74×1020 protons on target in upgraded NuMI beam at Fermilab, we observe 6 events Far Detector, compared a background expectation of 0.99±0.11(syst) based Near Detector measurement. A secondary analysis observes 11 with 1.07±0.14(syst). The 3.3σ excess observed primary disfavors 0.1π<δCP<0.5π inverted mass hierarchy 90% C.L.Received 19 January...
The Double Chooz experiment presents improved measurements of the neutrino mixing angle θ 13 using data collected in 467.90 live days from a detector positioned at an average distance 1050 m two reactor cores nuclear power plant. Several novel techniques have been developed to achieve significant reductions backgrounds and systematic uncertainties with respect previous publications, whereas efficiency $$ {\overline{\nu}}_e signal has increased. value is measured be sin2 2θ = 0.090 − 0.029 +...
The T2K experiment reports updated measurements of neutrino and antineutrino oscillations using both appearance disappearance channels. This result comes from an exposure $14.9(16.4)\ifmmode\times\else\texttimes\fi{}1{0}^{20}$ protons on target in (antineutrino) mode. Significant improvements have been made to the interaction model far detector reconstruction. An extensive set simulated data studies also performed quantify effect uncertainties oscillation parameter sensitivity. performs...
We present the results of indirect searches for Weakly Interacting Massive Particles (WIMPs), with 1679.6 live days data from Super-Kamiokande detector using neutrino-induced upward through-going muons. The search is performed by looking an excess high energy muon neutrinos WIMP annihilations in Sun, core Earth, and Galactic Center, as compared to number expected atmospheric neutrino background. No statistically significant was seen. calculate flux limits various angular cones around each...
A search for the relic neutrinos from all past core-collapse supernovae was conducted using 1496 days of data Super-Kamiokande detector. This analysis looked electron-type antineutrinos that had produced a positron with an energy greater than 18 MeV. In absence signal, 90% C.L. upper limits on total flux were set several theoretical models; these ranged 20 to 130 macro nu(e) cm(-2) s(-1). Additionally, bound 1.2 s(-1) supernova neutrino in region E(nu)>19.3
The time variation of the elastic scattering rate solar neutrinos with electrons in Super-Kamiokande-I was fit to variations expected from active two-neutrino oscillations. best large mixing angle solution has a tan2θ=0.55 and mass squared difference Δm2=6.3×10−5eV2 between two neutrino eigenstates. fitted day-night asymmetry −1.8±1.6(stat)+1.3−1.2(syst)% improved statistical precision over previous measurements agrees well −2.1%.Received 4 September...
We report the results of a search for ${\ensuremath{\nu}}_{\ensuremath{\mu}}$ disappearance by Main Injector Neutrino Oscillation Search [D. G. Michael et al. (MINOS), Phys. Rev. Lett. 97, 191801 (2006).]. The experiment uses two detectors separated 734 km to observe beam neutrinos created Neutrinos at facility Fermi National Accelerator Laboratory. data were collected in first 282 days operations and correspond an exposure $1.27\ifmmode\times\else\texttimes\fi{}{10}^{20}$ protons on target....
The relative sidereal variation in the arrival direction of primary cosmic ray nuclei median energy 10 TeV was measured using downward, through-going muons detected with Super-Kamiokande-I detector. projection anisotropy map onto right ascension axis has a first harmonic amplitude $(6.64\ifmmode\pm\else\textpm\fi{}0.98\text{ }\text{ }\mathrm{stat}\ifmmode\pm\else\textpm\fi{}0.55\text{ }\mathrm{syst})\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$ and phase at maximum...
We report on the results of a three-flavor oscillation analysis using Super-Kamiokande I atmospheric neutrino data, with assumption one mass scale dominance ($\ensuremath{\Delta}{m}_{12}^{2}=0$). No significant flux change due to matter effect, which occurs when neutrinos propagate inside Earth for ${\ensuremath{\theta}}_{13}\ensuremath{\ne}0$, has been seen either in multi-GeV ${\ensuremath{\nu}}_{e}$-rich sample or ${\ensuremath{\nu}}_{\ensuremath{\mu}}$-rich sample. Both normal and...
The velocity of a ∼3 GeV neutrino beam is measured by comparing detection times at the near and far detectors MINOS experiment, separated 734 km. A total 473 detector events was used to measure (v−c)/c=5.1±2.9×10−5 (at 68% C.L.). By correlating energies 258 charged-current their arrival detector, limit imposed on mass mν<50 MeV/c2 (99% C.L.).Received 4 June 2007DOI:https://doi.org/10.1103/PhysRevD.76.072005©2007 American Physical Society