T. Yoshioka
A5067070075- Particle physics theoretical and experimental studies
- Nuclear Physics and Applications
- Particle Detector Development and Performance
- Atomic and Subatomic Physics Research
- Radiation Detection and Scintillator Technologies
- High-Energy Particle Collisions Research
- Nuclear reactor physics and engineering
- Nuclear physics research studies
- Quantum, superfluid, helium dynamics
- Neutrino Physics Research
- Advanced NMR Techniques and Applications
- Astrophysics and Cosmic Phenomena
- Dark Matter and Cosmic Phenomena
- Quantum Chromodynamics and Particle Interactions
- Muon and positron interactions and applications
- Building energy efficiency and sustainability
- Renewable energy and sustainable power systems
- Particle Accelerators and Free-Electron Lasers
- Cosmology and Gravitation Theories
- Superconducting Materials and Applications
- Particle accelerators and beam dynamics
- Medical Imaging Techniques and Applications
- CCD and CMOS Imaging Sensors
- Computational Physics and Python Applications
- Advanced MRI Techniques and Applications
Kyushu University
2016-2025
Nippon Soken (Japan)
2023
High Energy Accelerator Research Organization
2010-2023
Yamagata University
2023
Waseda University
2023
The Graduate University for Advanced Studies, SOKENDAI
2020-2023
Nagoya University
1999-2023
Toneyama National Hospital
2023
Osaka University
2017-2023
RIKEN
2023
Experiment E949 at Brookhaven National Laboratory has observed three new events consistent with the decay K+→π+ν¯ν in pion momentum region 140<Pπ<199 MeV/c an exposure of 1.71×1012 stopped kaons estimated total background 0.93±0.17(stat)+0.32−0.24(syst) events. This brings number to seven. Combining this observation previous results, assuming spectrum predicted by standard model, results a branching ratio B(K+→π+ν¯ν)=(1.73+1.15−1.05)×10−10. An interpretation for alternative models...
This paper introduces a new approach to measure the muon magnetic moment anomaly |$a_{\mu} = (g-2)/2$| and electric dipole (EDM) |$d_{\mu}$| at J-PARC facility. The goal of our experiment is |$a_{\mu}$| using an independent method with factor 10 lower momentum, 20 smaller diameter storage-ring solenoid compared previous ongoing |$g-2$| experiments unprecedented quality storage field. Additional significant differences from present experimental include 1000 transverse emittance beam...
Three events for the decay K+→π+ν¯ν have been observed in pion momentum region below K+→π+π0 peak, 140<Pπ<199 MeV/c, with an estimated background of 0.93±0.17(stat.)+0.32−0.24(syst.) events. Combining this observation previously reported results yields a branching ratio B(K+→π+ν¯ν)=(1.73+1.15−1.05)×10−10 consistent standard model prediction.Received 18 August 2008DOI:https://doi.org/10.1103/PhysRevLett.101.191802©2008 American Physical Society
Evidence of a heavy neutrino, $\nu_H$, in the $K^+\to\mu^+\nu_H$ decays was sought using E949 experimental data with an exposure $1.70\times 10^{12}$ stopped kaons. With major background from radiative $K^+\to\mu^+\nu_\mu\gamma$ decay understood and suppressed, upper limits (90% C.L.) on neutrino mixing matrix element between muon $|U_{\mu H}|^2$, were set at level $10^{-7}$ to $10^{-9}$ for mass region 175 300 MeV/$c^2$.
An additional event near the upper kinematic limit for K+-->pi(+)nunu; has been observed by experiment E949 at Brookhaven National Laboratory. Combining previously reported and new data, branching ratio is B(K+-->pi(+)nunu;)=(1.47(+1.30)(-0.89))x10(-10) based on three events in pion momentum region 211<P<229 MeV/c. At measured central value of ratio, had a signal-to-background 0.9.
Experiment E949 at Brookhaven National Laboratory studied the rare decay \$K^+\to\pi^+\nu\bar{\nu}$ and other processes with an exposure of $1.77\times 10^{12}$ $K^+$'s. The data were analyzed using a blind analysis technique yielding one candidate event estimated background $0.30\pm0.03$ events. Combining this result observation two events by predecessor experiment E787 gave branching ratio ${\calB}(K^+\to\pi^+\nu\bar{\nu})=(1.47^{+1.30}_{-0.89})\times 10^{-10}$, consistent Standard Model...
Abstract The CALICE collaboration is developing highly granular electromagnetic and hadronic calorimeters for detectors at future energy frontier electron-positron colliders. After successful tests of a physics prototype, technological prototype the Analog Hadron Calorimeter has been built, based on design construction techniques scalable to collider detector. consists steel absorber structure active layers small scintillator tiles that are individually read out by directly coupled SiPMs....
As a new method to determine the resonance frequency, Rabi-oscillation spectroscopy has been developed. In contrast conventional which draws curve, fits time evolution of Rabi oscillation. By selecting optimized it is shown that precision twice as good with frequency sweep. Furthermore, data under different conditions can be treated in unified manner, allowing more efficient measurements for systems consisting limited number short-lived particles produced by accelerators such muons. We have...
We describe an experimental search for deviations from the inverse-square law of gravity at nanometer length scale using neutron scattering noble gases on a pulsed slow beam line. By measuring momentum transfer (q) dependence differential cross section xenon and helium comparing to their well-known analytical forms, we place upper bound strength new interaction as function λ which improves upon previous results in region λ<0.1 nm, remains competitive larger-λ region. A pseudoexperimental...
Angular distribution of individual $\gamma$-rays, emitted from a neutron-induced compound nuclear state via radiative capture reaction ${}^{139}$La(n,$\gamma$) has been studied as function incident neutron energy in the epithermal region by using germanium detectors. An asymmetry $A_{\mathrm{LH}}$ was defined $(N_{\mathrm L}-N_{\mathrm H})/(N_{\mathrm L}+N_{\mathrm H})$, where $N_{\mathrm L}$ and H}$ are integrals low high resonance respectively, we found that angular dependence...
The mass function and statistics of binaries provide important diagnostics the star formation process. Despite this importance, at low masses remains poorly known due to observational difficulties caused by faintness objects. Here we report microlensing discovery characterization a binary lens composed very low-mass stars just above hydrogen-burning limit. From combined measurements Einstein radius microlens parallax, measure components $0.10\pm 0.01\ M_\odot$ $0.09\pm M_\odot$. This...
Neutron transmission experiments can offer a new type of highly sensitive search for time-reversal invariance violating (TRIV) effects in nucleon-nucleon interactions via the same enhancement mechanism observed large parity (PV) neutron-induced compound nuclear processes. In these processes, TRIV cross section is given as product PV section, spin factor κ, and ratio matrix elements. We determined κ to be 0.59±0.05 139La+n using both (n,γ) spectroscopy (→n+139→La) transmission. This result...
Multiwavelength observations of the optical afterglow GRB 050319 were performed from 1.31 to 9.92 hr after burst. Our R-band light curves, combined with other published data, can be described by smooth broken power-law function, α1 = -0.84 ± 0.02 α2 -0.48 0.03, 0.04 days gamma-ray The curves are characterized shallow decays—as was also observed in X-rays—which may have a similar origin, related energy injection. However, our indicate that there is still puzzle concerning chromatic breaks...
A detailed study of hadronic interactions is presented using data recorded with the highly granular CALICE silicon-tungsten electromagnetic calorimeter. Approximately 350,000 selected negatively charged pion events at energies between 2 and 10 GeV have been studied. The predictions several physics models available within Geant4 simulation tool kit are compared to this data. reasonable overall description observed; Monte Carlo 20% data, for many observables much closer. largest quantitative...
A first prototype of a scintillator strip-based electromagnetic calorimeter was built, consisting 26 layers tungsten absorber plates interleaved with planes 45×10×3 mm3 plastic strips. Data were collected using positron test beam at DESY momenta between 1 and 6 GeV/c. The prototype׳s performance is presented in terms the linearity resolution energy measurement. These results represent an important milestone development highly granular calorimeters strip technology. number possible design...
An $sp$-mixing model, which describes a compound nuclear reaction by mixing partial waves, predicts correlation term in this reaction. A detailed study of the model is required to feasibility new type time reversal symmetry violation search experiment. The ${\mathbit{\ensuremath{\sigma}}}_{n}\ifmmode\cdot\else\textperiodcentered\fi{}({\mathbit{k}}_{n}\ifmmode\times\else\texttimes\fi{}{\mathbit{k}}_{\ensuremath{\gamma}})$ $^{139}\mathrm{La}(\stackrel{P\vec}{n},\ensuremath{\gamma})$ has been...
A neutron-energy dependent angular distribution was measured for individual $\ensuremath{\gamma}$ rays from the 3.2 eV $p$-wave resonance of $^{131}\mathrm{Xe}+n$, that shows enhanced parity violation owing to a mixing between $s$- and amplitudes. The $\ensuremath{\gamma}$-ray transitions were identified, with respect neutron momentum evaluated as function energy 7132 keV rays, which correspond transition 1807 excited state $^{132}\mathrm{Xe}$. is considered originate interference...