Atsushi Okada
A5083445762- Kidney Stones and Urolithiasis Treatments
- Astrophysics and Cosmic Phenomena
- Neutrino Physics Research
- Pediatric Urology and Nephrology Studies
- Particle physics theoretical and experimental studies
- Dark Matter and Cosmic Phenomena
- Ureteral procedures and complications
- Urological Disorders and Treatments
- Renal and Vascular Pathologies
- Bone and Dental Protein Studies
- Bladder and Urothelial Cancer Treatments
- Pancreatitis Pathology and Treatment
- Muon and positron interactions and applications
- Renal cell carcinoma treatment
- Urologic and reproductive health conditions
- Magnetic properties of thin films
- Chronic Kidney Disease and Diabetes
- Parathyroid Disorders and Treatments
- Particle Detector Development and Performance
- Porphyrin Metabolism and Disorders
- Prostate Cancer Diagnosis and Treatment
- Therapeutic Uses of Natural Elements
- Urinary Bladder and Prostate Research
- Gamma-ray bursts and supernovae
- Pelvic floor disorders treatments
Nagoya City University
2016-2025
Kyoto Prefectural University
2024
Osaka University
2024
Tohoku University
2001-2024
Minneapolis Heart Institute Foundation
2023-2024
National Cerebral and Cardiovascular Center
2016-2024
Mizuho (Japan)
2007-2024
Valve (United States)
2024
National Museum of Nature and Science
2024
City University of Seattle
2022
We present an analysis of atmospheric neutrino data from a 33.0 kton yr (535-day) exposure the Super-Kamiokande detector. The exhibit zenith angle dependent deficit muon neutrinos which is inconsistent with expectations based on calculations flux. Experimental biases and uncertainties in prediction fluxes cross sections are unable to explain our observation. consistent, however, two-flavor...
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 first results of the solar neutrino flux measurement from Super-Kamiokande are presented. shown here obtained data taken between 31 May 1996, and 23 June 1997. Using our recoil electrons with energies above 6.5 MeV, we infer total ${}^{8}\mathrm{B}$ neutrinos to be $2.42\ifmmode\pm\else\textpm\fi{}0.06(\mathrm{stat}{)}_{\ensuremath{-}0.07}^{+0.10}(\mathrm{syst})\ifmmode\times\else\texttimes\fi{}{10}^{6}\mathrm{cm}{}^{\ensuremath{-}2}{\mathrm{s}}^{\ensuremath{-}1}$. This result is...
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...
Muon neutrino disappearance probability as a function of flight length L over energy E was studied. A dip in the L/E distribution observed data, predicted from sinusoidal flavor transition oscillation. The constrained nu_mu <-> nu_tau oscillation parameters; 1.9x10^-3 < Delta m^2 3.0x10^-3 eV^2 and \sin^2(2theta) > 0.90 at 90% confidence level.
A total of 614 upward throughgoing muons minimum energy 1.6 GeV are observed by Super-Kamiokande during 537 detector live days. The measured muon flux is [1.74±0.07(stat)±0.02(sys)]×10−13cm−2s−1sr−1 compared to an expected [1.97±0.44(theor)]×10−13cm−2s−1sr−1. absolute in agreement with the prediction within errors. However, zenith-angle dependence does not agree no-oscillation predictions. distortion shape consistent νμ↔ντ oscillation hypothesis sin22θ>0.4 and 1×10−3<Δm2<1×10−1eV2 at 90%...
From an exposure of 25.5 kiloton-years the Super-Kamiokande detector, 900 muon-like and 983 electron-like single-ring atmospheric neutrino interactions were detected with momentum pe>100 MeV/c, pμ>200 visible energy less than 1.33 GeV. Using a detailed Monte Carlo simulation, ratio (μ/e)DATA/(μ/e)MC was measured to be 0.61±0.03(stat.)±0.05(sys.), consistent previous results from Kamiokande, IMB Soudan-2 experiments, smaller expected theoretical models production.
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 flavor ratio of the atmospheric neutrino flux and its zenith angle dependence have been studied in multi-GeV energy range using an exposure 25.5 kiloton-years Super-Kamiokande detector. By comparing data to a detailed Monte Carlo simulation, (μ/e)DATA/(μ/e)MC was measured be 0.66±0.06(stat.)±0.08(sys.). In addition, strong distortion shape μ-like event distribution observed. number upward downward events found 0.52+0.07−0.06(stat.)±0.01(sys.), with expected value...
A search for day-night variations in the solar neutrino flux resulting from oscillations has been carried out using 504 day sample of data obtained at Super-Kamiokande. The absence a significant variation set an absolute independent exclusion region two oscillation parameter space.
A measurement of the energy spectrum recoil electrons from solar neutrino scattering in Super-Kamiokande detector is presented. The results shown here were obtained 504 days data taken between 31 May 1996 and 25 March 1998. shape measured compared with expectation for ${}^{8}\mathrm{B}$ neutrinos. comparison takes into account both kinematic related effects process. spectral observation gives a ${\ensuremath{\chi}}^{2}$ 25.3 15 degrees freedom, corresponding to $4.6%$ confidence level.
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...
Rice diterpenoid phytoalexins such as momilactones and phytocassanes are produced in suspension-cultured rice cells treated with a chitin oligosaccharide elicitor leaves irradiated UV light. The common substrate geranylgeranyl diphosphate is converted into diterpene hydrocarbon precursors via two-step sequential cyclization then the bioactive several oxidation steps. It has been suggested that microsomal cytochrome P-450 monooxygenases (P-450s) involved downstream of hydrocarbons leading to...
The M2 protein of influenza A virus forms a homotetramer ion channel in the lipid membrane. is specific for proton conductance and activated by low pH with transition midpoint at 5.7. We have studied structure transmembrane domain using UV resonance Raman spectroscopy, special attention to side chains histidine (His37) tryptophan (Trp41) residues. spectra provide direct evidence that imidazole ring His37 protonated upon activation pH. Concomitantly, scattering from Trp41 shows an unusual...
Two is better than one: Novel chiral phosphine–olefin ligands 1 a and b act as bidentate with some transition metals have proved to be highly effective in the rhodium-catalyzed asymmetric 1,4-addition of aryl boronic acids maleimides high enantioselectivity (see scheme). Supporting information for this article available on WWW under http://www.wiley-vch.de/contents/jc_2002/2005/z501305_s.pdf or from author. Please note: The publisher not responsible content functionality any supporting...
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
Amorphous rare-earth RE(Gd, Tb, Dy, Ho, Er) -Fe films prepared by cosputtering were studied. The compositional analysis was obtained from known deposition profiles, x-ray microanalysis, and the stripe-width measurements. structural variation with composition change investigated electron diffraction dark-field microscopy. Curie temperature Tc, compensation Tcomp, coercive force Hc, uniaxial anisotropy energy Ku static domain properties such as stripe width Ws, wall σw, exchange stiffness...
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...