A5001015065- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Quantum Chromodynamics and Particle Interactions
- Particle Detector Development and Performance
- Radiation Detection and Scintillator Technologies
- Nuclear reactor physics and engineering
- Nuclear physics research studies
- Particle Accelerators and Free-Electron Lasers
- Atomic and Subatomic Physics Research
- Dark Matter and Cosmic Phenomena
- Superconducting Materials and Applications
- Medical Imaging Techniques and Applications
- Nuclear Physics and Applications
- Pediatric Urology and Nephrology Studies
- Neutrino Physics Research
- Statistical Methods and Bayesian Inference
- Computational Physics and Python Applications
- Particle accelerators and beam dynamics
- Magnetic confinement fusion research
- Gamma-ray bursts and supernovae
- Simulation Techniques and Applications
- Optical properties and cooling technologies in crystalline materials
- Robotics and Automated Systems
- nanoparticles nucleation surface interactions
- Advanced X-ray Imaging Techniques
Institute of Physics, Academia Sinica
2022-2023
High Energy Accelerator Research Organization
2015-2023
The University of Tokyo
2012-2022
Tokyo University of Science
2012-2022
Institute of Particle and Nuclear Studies
2017-2022
Osaka University
2013-2022
RIKEN Nishina Center
2014-2019
Campbell Collaboration
2017
Japan Atomic Energy Agency
2016
RIKEN
2014-2015
Abstract Chiral symmetry and its spontaneous breaking is an essential property of the QCD vacuum closely related to generation hadron mass. J-PARC E16 experiment measures dielectron spectra in p+A collisions at 30 GeV study in-medium spectral change vector mesons that signals partial restoration broken symmetry. The uses primary proton beam available high-momentum line experimental facility. We performed three proton-beam runs intended for beamline detector commissioning. are preparing next...
The exclusive reaction γp→K(+)π(-)Σ(+) was measured for the first time using linearly polarized photons at beam energies from 1.85 to 2.96 GeV. Angular distributions in rest frame of K(+)π(-) system were fitted extract spin-density matrix elements K(*0) decay. parity spin asymmetry shows that natural-parity exchange is dominant this reaction. This result clearly indicates need t-channel κ(800) scalar meson.
The $\phi$-$\Lambda(1520)$ interference effect in the $\gamma p\to K^+K^-p$ reaction has been measured for first time energy range from 1.673 to 2.173 GeV. relative phases between $\phi$ and $\Lambda(1520)$ production amplitudes were obtained kinematic region where two resonances overlap. measurement results support strong constructive when $K^+K^-$ pairs are observed at forward angles, but destructive proton emission angles. Furthermore, does not account $\sqrt{s}=2.1$ GeV bump structure...
The J-PARC Hadron Experimental Facility was constructed with an aim to explore the origin and evolution of matter in universe through experiments intense particle beams. In past decade, many results on nuclear physics have been obtained at present facility. To expand programs unexplored regions never achieved, extension project has extensively discussed. This white paper presents for resolving issues fields strangeness physics, hadron flavor physics.
We report the measurement of $\gamma p \rightarrow K^{+}\Lambda$ and K^{+}\Sigma^{0}$ reactions at SPring-8. The differential cross sections photon-beam asymmetries are measured forward $K^{+}$ production angles using linearly polarized tagged-photon beams in range $E_{\gamma}=1.5$--3.0 GeV. With increasing photon energy, for both decrease slowly. Distinct narrow structures section have not been found peaking angular distributions sections, a characteristic feature $t$-channel exchange, is...
Differential cross sections at t=tmin and decay asymmetries for the γp→ϕp reaction have been measured using linearly polarized photons in range 1.5 to 2.9 GeV. These were used determine Pomeron strength factor. The are consistently described by t-channel pseudoscalar exchange model Eγ region above 2.37 In lower energy region, an excess over prediction is observed dependence of differential t=tmin. This observation suggests that additional processes or interference effects between other...
We report the measurement of differential cross sections for $\omega$ and $\eta'$ photoproduction from protons at backward angles ($-1.0<\cos\Theta_{C.M}^{X}<-0.8$) using linearly polarized photons $E_{\gamma}=$$1.5-3.0$ GeV. Differential mesons are larger than predicted $u$-channel contribution in energy range $2.0\leq\sqrt{s}\leq2.4$ The become closer to $\sqrt{s}>2.4$ A bump structure $\sqrt{s}$ dependence was observed $\sqrt{s}\sim$2.35
RHIC-PHENIX has observed a large suppression pattern and azimuthal anisotropy of non-photonic electron at mid-rapidity ($\mid\eta\mid<0.35$) in Au+Au collisions $\sqrt{s_{NN}} = 200$ GeV. To understand these results the interaction heavy quarks hot dense medium, experimental determination production ratio charm over bottom is one most important topics, since behavior may differ from medium. We measured total cross section via partial reconstruction D$^0$$\to$e$^+$ K$^-$ $\nu_e$ decay p+p...
The differential cross sections and decay angular distributions for coherent $\phi$-meson photoproduction from helium-4 have been measured the first time at forward angles with linearly polarized photons in energy range $E_{\gamma} = \text{1.685-2.385 GeV}$. Thanks to target spin-parity $J^{P} 0^{+}$, unnatural-parity exchanges are prohibited, thus natural-parity can be investigated clearly. asymmetry respect photon polarization is shown very close maximal value. This ensures dominance ($>...
Differential cross sections and photon-beam asymmetries for the →γp→π+n reaction have been measured 0.6<cosθπ<1 Eγ=1.5–2.95GeV at SPring-8/LEPS. The monotonically decrease as photon beam energy increases 0.6<cosθπ<0.9. However, dependence of 0.9<cosθπ<1 Eγ=1.5–2.2GeV (W=1.9–2.2GeV) is different, which may be due to a nucleon or Δ resonance. present agree well with previous by other groups show forward peaking, suggesting significant t-channel contributions in this kinematical region. are...
The heavy quark baryon spectroscopy is an essential ways to understand the hadron structure. In case of charmed baryon, two light quarks are isolated and form diquark correlation due small color-magnetic interaction between charm lighter quarks. excitation modes from reflected structure excited spectrum decay states. addition, by measuring ratio cross section ground state Λc + states, information inside such as configuration spin/isospin states can be obtained [1]. From systematic study...
Differential cross sections and photon-beam asymmetries for the gamma p -> pi- Delta++(1232) reaction have been measured 0.7<cos(theta)<1 Egamma=1.5-2.95 GeV at SPring-8/LEPS. The first-ever high statistics section data are obtained in this kinematical region, asymmetry 1.5<Egamma(GeV)<2.8 first time. This has a unique feature studying production mechanisms of pure $u\bar{u}$ quark pair final state from proton. Although there is no distinct peak structure sections, non-negligible excess over...
1 RIKEN Nishina Center, RIKEN, Saitama 351-0198, Japan 2KEK, High Energy Accelerator Research Organization, Ibaraki 305-0801, 3Center for Nuclear Study, Graduate School of Science, University Tokyo, Tokyo 113-0033, 4Department Physics, 5Japan Synchrotron Radiation Institute, Hyogo 679-5198, 6Department Kyoto University, 7Hiroshima Hiroshima 739-8526, 8Research Center Osaka Ibaraki, 567-0047,
At the J-PARC E16 experiment[1], we measure mass spectra of vector mesons in nuclei from e+e- decay channel with high precision and statistics. We have developed trigger system consisting newly ASD ASICs which can extract signals GEM foil used as a cathode plane induction gap chamber digital electronics using FPGAs processes binary ASIC.
A project to study high-density nuclear matter using heavy ion collisions in a beam energy range of few GeV is being prepared at J-PARC. The goal the perform experiments with energies 1-12 AGeV/c and collision rate 10 11 Hz. divided into two phases. For first stage, measurements limited intensity will be performed upgraded spectrometer an on-going experiment. Full performance implemented second phase detail high density light hypernuclei. Feasibility for both phases are evaluated.
The heavy quark baryon spectroscopy is a key way to understand what the building block of hadrons is. diquark correlation which expectedly an essential degree freedom describe hadron structure can be investigated from charmed baryons. An experiment observe and investigate baryons was proposed at J-PARC high- momentum beam line. missing mass via π− p → Y*+c D*− reaction 20 GeV/c will performed for systematic measurement excitation energy, production rates decay products In addition,...
We developed a Lambertson magnet and two septum magnets as the splitting devices for new beamline at Hadron Experimental Facility in J-PARC. This beamline, now under construction, is called high-p/COMET experiments using 30- 8-GeV proton beams are planned. The required functions of follows: to split small fraction (around 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−4</sup> ) 30-GeV beam into (30-GeV mode) bend all (8-GeV mode). These...
The J-PARC E16 experiment was proposed to investigate the restoration of chiral symmetry at normal nuclear density. will systematically measure in-medium mass vector mesons Hadron Experimental Facility using a 30-GeV proton beam with an intensity 2 x 1010 protons per pulse. spectrometer designed detect e+e- from slowly moving meson, particularly ϕ meson. detector system consists GEM tracker, Gas Cerenkov based on and electromagnetic calorimeter made lead-glass, whose number channels reaches...