Yuya Fujiwara
A5021796089- Quantum Chromodynamics and Particle Interactions
- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Nuclear physics research studies
- Ionosphere and magnetosphere dynamics
- High-pressure geophysics and materials
- Quantum, superfluid, helium dynamics
- Ion-surface interactions and analysis
- Atomic and Subatomic Physics Research
- Carbon Nanotubes in Composites
- Tissue Engineering and Regenerative Medicine
- Seismic Waves and Analysis
- Earthquake Detection and Analysis
- Solar and Space Plasma Dynamics
- Geophysics and Gravity Measurements
- Diamond and Carbon-based Materials Research
- Superconducting Materials and Applications
- Nuclear Physics and Applications
- Particle Detector Development and Performance
- Advanced NMR Techniques and Applications
- Congenital heart defects research
- Cardiomyopathy and Myosin Studies
- Nuclear reactor physics and engineering
- Magnetic confinement fusion research
- Electrospun Nanofibers in Biomedical Applications
The University of Tokyo
2013-2024
Kyoto University
1993-2024
Takeda (Japan)
2023
Osaka Red Cross Hospital
2023
Kyoto Bunkyo University
2021
Bunkyo University
2019-2020
University of Hyogo
2015-2019
Shibaura Institute of Technology
2014-2017
Tottori University
2014
Kyushu University
2007
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...
Abstract One of the earliest maturation steps in cardiomyocytes (CMs) is sarcomere protein isoform switch between TNNI1 and TNNI3 (fetal neonatal/adult troponin I). Here, we generate human induced pluripotent stem cells (hiPSCs) carrying a EmGFP mCherry double reporter to monitor isolate mature sub-populations during cardiac differentiation. Extensive drug screening identifies two compounds, an estrogen-related receptor gamma (ERRγ) agonist S-phase kinase-associated 2 inhibitor, that...
We have performed an exclusive measurement of the K−+He3→Λpn reaction at incident kaon momentum 1GeV/c. In Λp invariant mass spectrum, a clear peak was observed below threshold K¯+N+N, as signal kaonic nuclear bound state, K¯NN. The binding energy, decay width, and S-wave Gaussian form factor this state were to be BK=42±3(stat.)−4+3(syst.)MeV, ΓK=100±7(stat.)−9+19(syst.)MeV, QK=383±11(stat.)−1+4(syst.)MeV/c, respectively. total production cross section K¯NN, determined by its mode,...
An experiment to search for the $K^-pp$ bound state was performed via in-flight $^3$He($K^-,n)$ reaction using 5.3 $\times$ $10^9$ kaons at 1 GeV/$c$ J-PARC hadron experimental facility. In semi-inclusive neutron missing-mass spectrum $\theta_{n}^{lab}=0^\circ$, no significant peak observed in region corresponding binding energy larger than 80 MeV, where a bump structure has been reported $\Lambda p$ final different reactions. Assuming be isotropically decaying into p$, mass-dependent upper...
The semiclassical distorted wave model is developed to describe(π−,K+) inclusive spectra related Σ− formationmeasured at KEK with pπ=1.2 GeV/c. shape and magnitudeof the spectrum obtained a 28Si target are satisfactorilyreproduced using repulsive Σ-nucleus potential whose strengthis of order 30-50 MeV. This strength not as largeas value more than 100 MeV estimationpresented in report experiment.
Three beam lines for secondary charged particles are constructed in the hadron experimental hall of J-PARC. The K1.8 line, which incorporates two separators, delivers clean beams kaons up to 2 GeV/c. K1.8BR line is a branch K1.8, low-momentum 1.2 K1.1BR shorter designed kaons. Details these designs, as well commissioning results, described.
We measured a set of $\pi^\pm\Sigma^\mp$, $\pi^0\Sigma^0$, and $\pi^-\Sigma^0$ invariant mass spectra below above the $\bar{K}N$ threshold in $K^-$-induced reactions on deuteron. deduced $S$-wave $\bar{K}N\rightarrow\pi\Sigma$ $\bar{K}N\rightarrow\bar{K}N$ scattering amplitudes isospin 0 channel framework $\pi\Sigma$ coupled channel. find that resonance pole corresponding to $\Lambda(1405)$ is located at 1417.7$^{+6.0}_{-7.4}$(fitting errors)$^{+1.1}_{-1.0}$(systematic errors) +...
Abstract We perform a self‐consistent one‐dimensional electromagnetic particle simulation with uniform magnetic field and open boundaries. The plasma environment consists of cold isotropic electrons, energetic immobile ions. electrons are initialized subtracted‐Maxwellian distribution temperature anisotropy. By oscillating external currents constant frequency 0.2 f ce , where is the electron cyclotron frequency, whistler‐mode wave injected as triggering from center system, we investigated...
Engineered cardiac tissue (ECT) using human induced pluripotent stem cell-derived cardiomyocytes is a promising tool for modeling heart disease. However, immaturity makes robust disease difficult. Here, we established method hypertrophic cardiomyopathy (HCM) malignant (MYH7 R719Q) and nonmalignant (MYBPC3 G115∗) pathogenic sarcomere gene mutations by accelerating ECT maturation an ERRγ agonist, T112, mechanical stretching. ECTs treated with T112 under 10% elongation stimulation exhibited...
A new spectrometer system has been designed and constructed at the secondary beam line K1.8BR in hadron hall of J-PARC to investigate |$\bar {K} N$| interactions {K}$|-nuclear bound systems. The consists a high precision spectrometer, liquid 3He/4He/D2 target system, cylindrical detector that surrounds detect decay particles from region, neutron time-of-flight counter array located ∼15 m downstream position. Details design, construction, performance components are described.
We solve the neutron-deuteron (nd) scattering in Faddeev formalism, employing NN sector of quark-model baryon-baryon interaction fss2. The energy dependence interaction, inherent to resonating-group formulation is eliminated by standard off-shell transformation utilizing normalization kernel two-cluster systems. An extra nonlocality originating from this procedure very important reproduce all nd observables below En ≤ 65 MeV. A new algorithm Alt-Grassberger-Sandhas (AGS) equations presented...
Abstract We perform an electromagnetic particle simulation of triggered emissions in a uniform magnetic field for understanding nonlinear wave–particle interaction the vicinity equator. A finite length whistler-mode triggering wave packet with constant frequency is injected by oscillating external current at find that first subpacket generated homogeneous field. By analyzing resonant currents and electron dynamics simulation, we formation hole velocity phase space results currents, cause...
Data on the production of η mesons light nuclei near threshold are surveyed.The photoproduction 3 He and elastic scattering from this nucleus modelled in a multiple scheme positions poles both here neighbouring studied an optical potential approach.The 7 Li is compared to that within cluster model.The decay η-mesic through pion or nucleon emission also considered.
The S-wave effective-range parameters of the neutron-deuteron (nd) scattering are calculated in Faddeev formalism using a nonlocal Gaussian potential based on quark-model baryon-baryon interaction fss2. spin-doublet low-energy eigenphase shift is sufficiently attractive to reproduce predictions by AV18 plus Urbana three-body force, yielding almost correct values length and triton binding energy without three-nucleon force. This feature due strong distortion effect deuteron this spin channel,...
We continue the previous quark-model studies of qq pair-creation transition amplitudes for P-wave baryons and evaluate energy shifts compact 3q energies due to couplings baryon-meson composite configurations. These configurations are described by antisymmetrized (3q)(qq) cluster-model wave functions composed simple harmonic oscillator plane-wave relative motion. The rich spin-flavor SU6 structure off-shell Fermi-Breit interaction threshold effects various predict non-uniform each member...
The J-PARC E15 experiment aims to search for the lightest kaonic nuclear states, namely K - pp, using in-flight (K , n) reaction on 3 He . In this experiment, missing mass in and invariant of decay such as pp → Λp pπ p will be measured simultaneously. article, experimental feature present status are presented.
Abstract. We measured πE invariant mass spectra below and above the K¯N threshold in K − d → NπE reaction order to study interaction Λ(1405) resonance. This can be described by two-step process: (i) 1 followed (ii) 2 πΣ, where N are nucleons bound deuteron. deduced S -wave scattering amplitude of framework πΣ coupled channel so as reproduce observed π Σ I = 0 channel. found a resonance pole at 1417.7 -7.4 +6.0 (fitting error) -1.0 +1.1 (systematic - i[26.9 -7.9 -2.0 +1.7 error)]MeV/ c .
We conducted measurements of $K^- + {^3{\rm He}} \to \pi \!Y \!N N'$ reactions using $1~{\rm GeV}/c$ $K^-$-beam, aiming to understand the broad decay width $\bar{K} \!N$ ($\approx$ twice as that $\Lambda(1405)$ considered be quasi-bound state). successfully reproduced distributions $\pi \! Y N$ invariant mass and momentum transfer by employing model fitting functions for N formation quasi-free $\bar{K}$ absorption (${\rm QF}_{\bar{K}-{\rm abs}}$) processes. The can describe experimental data...
Abstract Background The major cause of mortality in patients with Duchenne muscular dystrophy (DMD) is cardiomyopathy. This disease caused by dystrophin gene mutations that result the loss protein. Gene replacement therapies have been approved for skeletal muscle symptoms DMD. However, these therapeutic modalities are not indicated cardiomyopathy due to their low efficiency delivery heart. Despite significant unmet needs, a limitation this area research divergence model animals from those...
Abstract Background Engineered cardiac tissue (ECT) utilizing human induced pluripotent stem cell derived cardiomyocytes (hiPSC-CMs) is anticipated to function as a translational in vitro model. However, hiPSC-CMs display phenotypes indicative of immaturity, and the structural organization ECT composed insuficient when compared that mature adult hearts. Although mechanisms for maturation have been reported, little known about regulating formation such ECT. Cell adhesion molecules play...
Human induced pluripotent stem cells derived cardiomyocytes (hiPSC-CMs) can recapitulate the properties of human cardiomyocyte and exhibit disease phenotypes in vitro, attributable to their healthy- or patient-specific genetic backgrounds. Therefore, hiPSC-CMs are a crucial tool for developing therapeutic agents cardiovascular diseases, regenerative medicine using is expected be an alternative therapy heart transplantation. Moreover, development organoid models has been advanced replicate...