A5068893974- Quantum Chromodynamics and Particle Interactions
- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Nuclear physics research studies
- Atomic and Subatomic Physics Research
- Atomic and Molecular Physics
- Muon and positron interactions and applications
- Superconducting and THz Device Technology
- Physics of Superconductivity and Magnetism
- Quantum, superfluid, helium dynamics
- High-pressure geophysics and materials
- Particle accelerators and beam dynamics
- Superconducting Materials and Applications
- Particle Detector Development and Performance
- X-ray Spectroscopy and Fluorescence Analysis
- Ionosphere and magnetosphere dynamics
- Cold Atom Physics and Bose-Einstein Condensates
- Nuclear Physics and Applications
- Magnetic confinement fusion research
- Geophysics and Gravity Measurements
- Particle Accelerators and Free-Electron Lasers
- Advanced Chemical Physics Studies
- Dark Matter and Cosmic Phenomena
- Earthquake Detection and Analysis
- Superconductivity in MgB2 and Alloys
Chubu University
2020-2025
RIKEN
2014-2024
Pioneer (Japan)
2018-2024
Tokyo Institute of Technology
2005-2022
RIKEN Nishina Center
2009-2020
The University of Tokyo
1982-2019
Jagiellonian University
2015-2019
Institute of Physics
2015-2019
Sapienza University of Rome
2015-2019
Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Frascati
2009-2019
The $\bar{K}N$ system at threshold is a sensitive testing ground for low energy QCD, especially the explicit chiral symmetry breaking. Therefore, we have measured $K$-series x rays of kaonic hydrogen atoms DA$\Phi$NE electron-positron collider Laboratori Nazionali di Frascati, and determined most precise values strong-interaction energy-level shift width $1s$ atomic state. As x-ray detectors, used large-area silicon drift detectors having excellent timing resolution, which were developed...
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...
We have measured the proton energy distribution from 4He(stopped K−,p) reaction by means of time-of-flight. A mono-energetic peak was observed, which is interpreted as formation a new kind neutral tribaryon S0(3115) with isospin T=1 and strangeness S=−1. The mass width state were deduced to be 3117.0−4.4+1.5MeV/c2 <21MeV/c2, respectively. mainly decays into ΣNN.
Kaonic atoms are exotic atomic systems where an electron is replaced by a negatively charged kaon which also experiences the strong interaction with nucleus. Precision spectroscopy of kaonic represents excellent tool to study particles strangeness. This work reviews progress and prospects in modern era atom experiments, discusses constraints on low-energy theories strangeness sector.
We observed a distinct peak in the Λp invariant mass spectrum of He3(K−,Λp)n, well below mK+2mp, i.e., threshold K− to be bound two protons. By selecting relatively large momentum-transfer region q=350∼650 MeV/c, one can kinematically separate from quasi-free process, K‾N→K‾N followed by non-resonant absorption spectator-nucleons K‾NN→ΛN. found that simplest fit gives us Breit–Wigner pole position at BKpp=47±3(stat.)−6+3(sys.) MeV having width ΓKpp=115±7(stat.)−20+10(sys.) MeV, and S-wave...
PAX (antiProtonic Atom X-ray spectroscopy) is a new experiment with the aim to test strong-field quantum electrodynamics (QED) effects by performing high-precision x-ray spectroscopy of antiprotonic atoms. By utilizing advanced microcalorimeter detection techniques and low-energy antiproton beam provided ELENA ring at CERN, gaseous targets will be used for creation atoms, measurement transitions between circular Rydberg states conducted up two orders magnitude improved accuracy over previous...
We have measured the Balmer-series x-rays of kaonic $^4$He atoms using novel large-area silicon drift x-ray detectors in order to study low-energy $\bar{K}$-nucleus strong interaction. The energy $3d \to 2p$ transition was determined be 6467 $\pm$ 3 (stat) 2 (syst) eV. resulting strong-interaction energy-level shift is agreement with theoretical calculations, thus eliminating a long-standing discrepancy between theory and experiment.
A model where a Dirac fermion is coupled to background dilaton field considered study s-wave scattering of by back ground black hole. It found that an uncomfortable situation towards information loss scenario arises when one loop correction gets involved during bosonization.
Emission of muonium (|$\mu ^+e^-$|) atoms from a laser-processed aerogel surface into vacuum was studied for the first time. Laser ablation used to create hole-like regions with diameter about 270 |$\mu $|m in triangular pattern hole separation range 300–500 $|m. The emission probability sample is at least eight times higher than uniform one.
The x-ray spectroscopy of the muonic atom has attracted atomic, nuclear, and particle physicists since its discovery. properties a atom, such as binding energy or atomic radius, are different from an ordinary because difference in mass between muon electron. Our collaboration employed superconductor transition-edge sensor (TES) microcalorimeters for atom. Thanks to recent detector development, 44-keV lines Ar, which is important precision test bound-state quantum electrodynamics, 76-keV Si,...
On the basis of chemical and physicochemical evidence, structures two antifungal oligoglycosides, echinoside A B from sea cucumber Actinopyga echinites (JAEGER), have been elucidated as 5 3, respectively.
The kaonic (3)He and (4)He X-rays emitted in the [Formula: see text] transitions were measured SIDDHARTA experiment. widths of 2p states determined to be text], respectively. Both results are consistent with theoretical predictions. width is much smaller than value by experiments performed 70's 80's, while was for first time.
We have measured the 3d→2p transition x rays of kaonic ^{3}He and ^{4}He atoms using superconducting transition-edge-sensor microcalorimeters with an energy resolution better than 6 eV (FWHM). determined energies to be 6224.5±0.4(stat)±0.2(syst) 6463.7±0.3(stat)±0.1(syst) eV, widths 2.5±1.0(stat)±0.4(syst) 1.0±0.6(stat)±0.3(stat) for ^{4}He, respectively. These values are nearly 10 times more precise in previous measurements. Our results exclude large strong-interaction shifts that suggested...
We have simultaneously measured the energy spectra of neutrons and protons emitted in non-mesonic weak decays HeΛ5 CΛ12 hypernuclei produced via (π+,K+) reaction with much higher statistics than those previous experiments. The neutron-to-proton yield ratios for both at a high threshold (60 MeV) were approximately equal to two, which suggests that ratio neutron- proton-induced decay channels, Γn(Λn→nn)/Γp(Λp→np), is about 0.5. In neutron spectra, we found low-energy component unexpectedly...
We performed a coincidence measurement of two nucleons emitted from the nonmesonic weak decay $_{\ensuremath{\Lambda}}^{5}\mathrm{He}$ formed via $^{6}\mathrm{Li}({\ensuremath{\pi}}^{+},{K}^{+})$ reaction. The energies and pair number distributions in opening angle between them were measured. In both $np$ $nn$ pairs, we observed clean back-to-back correlation coming two-body reactions $\ensuremath{\Lambda}p\ensuremath{\rightarrow}np$ $\ensuremath{\Lambda}n\ensuremath{\rightarrow}nn$,...
We have measured the angular correlation of pair nucleons np and nn emitted from nonmesonic weak decay (NMWD) ^{12}_{Lambda}C produced via (pi^+,K^+) reaction in coincidence measurement. The Lambda p -> n modes were clearly identified by measuring back-to-back nucleon pairs which is characteristic two-body kinematics. From numbers N_{nn} N_{np}, ratio Gamma_n/Gamma_p partial widths Gamma_n(Lambda nn) Gamma_p(Lambda np) was extracted to be 0.51+-0.13(stat) +- 0.05(syst); this result almost...
We have observed an intense high-energy component in inclusive He4(stopped K−,d) spectrum. For back-to-back Λd pairs a prominent event cluster has been found just below the m4He+mK−−mn mass threshold invariant spectrum of Λdn events, which is evidence for three-nucleon absorption process K− He4. In addition, appreciable strength revealed ~3220 MeV/c2. Well separated Σ0dn events show peak similar to case Λdn.Received 5 September 2007DOI:https://doi.org/10.1103/PhysRevC.76.068202©2007 American...