K. Nishimura
A5009204814- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Particle Detector Development and Performance
- Neutrino Physics Research
- Dark Matter and Cosmic Phenomena
- Radiation Detection and Scintillator Technologies
- Astrophysics and Cosmic Phenomena
- Particle Accelerators and Free-Electron Lasers
- Computational Physics and Python Applications
- Medical Imaging Techniques and Applications
- Atomic and Subatomic Physics Research
- Nuclear Physics and Applications
- Superconducting Materials and Applications
- Advanced X-ray Imaging Techniques
- Nuclear physics research studies
- X-ray Spectroscopy and Fluorescence Analysis
- Particle accelerators and beam dynamics
- CCD and CMOS Imaging Sensors
- Crystallography and molecular interactions
- Advanced Optical Sensing Technologies
- Cosmology and Gravitation Theories
- Photonic and Optical Devices
University of Hawaiʻi at Mānoa
2012-2024
University of Hawaii System
2012-2024
Kitasato University
1999-2024
Duke University
2022
Chonnam National University
2022
University of the Basque Country
2022
Kyoto University
1969-2022
Campbell Collaboration
2012-2022
University of Bonn
2012-2022
University of California, Berkeley
1957-2022
We report the observation of two narrow structures in mass spectra pi+-Y(nS) (n=1,2,3) and pi+-hb(mP)(m$ (m=1,2) pairs that are produced association with a single charged pion Y(5S) decays. The measured masses widths averaged over five final states M_1=(10607.2+-2.0) MeV/c2, Gamma_1=(18.4+-2.4) MeV M_2=(10652.2+-1.5) Gamma_2=(11.5+-2.2) MeV. results obtained 121.4 1/fb data sample collected Belle detector vicinity resonance at KEKB asymmetric-energy e+e- collider.
The Belle detector at the KEKB electron-positron collider has collected almost 1 billion Y(4S) events in its decade of operation. Super-KEKB, an upgrade is under construction, to increase luminosity by two orders magnitude during a three-year shutdown, with ultimate goal 8E35 /cm^2 /s luminosity. To exploit increased luminosity, been proposed. A new international collaboration Belle-II, being formed. Technical Design Report presents physics motivation, basic methods accelerator upgrade, as...
We study B→K(*)ℓ+ℓ− decays (ℓ=e, μ) based on a data sample of 657×106 BB¯ pairs collected with the Belle detector at KEKB e+e− collider. report differential branching fraction, isospin asymmetry, K* polarization, and forward-backward asymmetry (AFB) as functions q2=Mℓℓ2c2. The fitted AFB spectrum exceeds standard model expectation by 2.7 deviations. measured fractions are B(B→K*ℓ+ℓ−)=(10.7−1.0+1.1±0.9)×10−7 B(B→Kℓ+ℓ−)=(4.8−0.4+0.5±0.3)×10−7, where first errors statistical second systematic,...
Abstract Observations have found black holes spanning 10 orders of magnitude in mass across most cosmic history. The Kerr hole solution is, however, provisional as its behavior at infinity is incompatible with an expanding universe. Black models realistic predict that the gravitating a can increase expansion universe independently accretion or mergers, manner depends on hole’s interior solution. We test this prediction by considering growth supermassive elliptical galaxies over 0 < z ≲...
We report a measurement of the process $\ensuremath{\gamma}{\ensuremath{\gamma}}^{*}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{0}$ with $759\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ data sample recorded Belle detector at KEKB asymmetric-energy ${e}^{+}{e}^{\ensuremath{-}}$ collider. The pion transition form factor, $F({Q}^{2})$, is measured for kinematical region $4\text{ }{\mathrm{GeV}}^{2}\ensuremath{\lesssim}{Q}^{2}\ensuremath{\lesssim}40\text{ }{\mathrm{GeV}}^{2}$, where...
We report the first observations of spin-singlet bottomonium states hb(1P) and hb(2P). The are produced in reaction e+e−→hb(nP)π+π− using a 121.4 fb−1 data sample collected at energies near Υ(5S) resonance with Belle detector KEKB asymmetric-energy e+e− collider. determine M[hb(1P)]=(9898.2+1.1+1.0−1.0−1.1) MeV/c2 M[hb(2P)]=(10 259.8±0.6+1.4−1.0) MeV/c2, which correspond to P-wave hyperfine splittings ΔMHF=(+1.7±1.5) (+0.5+1.6−1.2) respectively. significances hb(2P) 5.5σ 11.2σ, find that...
The process $\gamma \gamma \to \phi \jpsi$ is measured for $\phi masses between threshold and 5 GeV/${\it c}^2$, using a data sample of 825 fb$^{-1}$ collected with the Belle detector. A narrow peak $8.8^{+4.2}_{-3.2}$ events, significance 3.2 standard deviations including systematic uncertainty, observed. mass natural width structure (named X(4350)) are to be $(4350.6^{+4.6}_{-5.1}(\rm{stat})\pm 0.7(\rm{syst})) \hbox{MeV}/{\it c}^2$ $(13^{+18}_{-9}(\rm{stat})\pm 4(\rm{syst})) \hbox{MeV}$,...
Free-electron lasers (FELs) present new challenges for camera development compared with conventional light sources. At SLAC a variety of technologies are being used to match the demands Linac Coherent Light Source (LCLS) and support wide range scientific applications. In this paper an overview X-ray detector design requirements at FELs is presented various cameras in use described benefit users planning experiments or analysts looking data. Features operation CSPAD camera, which currently...
We present a measurement of the charmless semileptonic decay $B^0\to\pi^-\ell^+\nu$ using data sample containing 657$\times 10^6$ $B\bar{B}$ events collected with Belle detector at KEKB asymmetric-energy $e^+e^-$ collider operating near $\Upsilon(4S)$ resonance. determine total branching fraction decay, $\mathcal{B}(B^0\to\pi^-\ell^+\nu)=(1.49\pm 0.04{(\mathrm{stat})}\pm 0.07{(\mathrm{syst})})\times 10^{-4}$. also report new precise differential rate, and extract Cabibbo-Kobayashi-Maskawa...
We present a precise measurement of the CP violation parameter sin2phi_1 and direct A_f using final data sample 772x10^6 B\bar B pairs collected at Upsilon(4S) resonance with Belle detector KEKB asymmetric-energy e+e- collider. One neutral meson is reconstructed in J/psi K0S, psi(2S) chi_c1 K0S or K0L CP-eigenstate its flavor identified from decay products accompanying meson. From distribution proper time intervals between two decays, we obtain following parameters:...
Abstract Objective. Decoding neural activity has been limited by the lack of tools available to record from large numbers neurons across multiple cortical regions simultaneously with high temporal fidelity. To this end, we developed Argo system at data rates. Approach. Here demonstrate a massively parallel recording based on platinum-iridium microwire electrode arrays bonded CMOS voltage amplifier array. The is highest channel count in vivo system, supporting simultaneous 65 536 channels,...
The Payload for Ultrahigh Energy Observations (PUEO) long-duration balloon experiment is designed to have world-leading sensitivity ultrahigh-energy neutrinos at energies above 1 EeV. Probing this energy region essential understanding the extreme-energy universe all distance scales. PUEO leverages experience from and supersedes successful Antarctic Impulsive Transient Antenna (ANITA) program, with an improved design that drastically improves by more than order of magnitude below 30 will...
Abstract The assembly of stellar and supermassive black hole (SMBH) mass in elliptical galaxies since z ∼ 1 can help to diagnose the origins locally observed correlations between SMBH mass. We therefore construct three samples galaxies, one at 0 two 0.7 ≲ 2.5, quantify their relative positions M BH − * plane. Using a Bayesian analysis framework, we find evidence for translational offsets both local sample higher-redshift samples. are small, consistent with measurement bias, but much larger,...
We present a study of $B\ensuremath{\rightarrow}X(3872)K$ with $X(3872)$ decaying to ${D}^{*0}{\overline{D}}^{0}$ using sample $657\ifmmode\times\else\texttimes\fi{}{10}^{6}$ $B\overline{B}$ pairs recorded at the $\ensuremath{\Upsilon}(4S)$ resonance Belle detector KEKB asymmetric-energy ${e}^{+}{e}^{\ensuremath{-}}$ collider. Both ${D}^{*0}\ensuremath{\rightarrow}{D}^{0}\ensuremath{\gamma}$ and ${D}^{*0}\ensuremath{\rightarrow}{D}^{0}{\ensuremath{\pi}}^{0}$ decay modes are used. find peak...
We present a new measurement of the unitarity triangle angle phi3 using Dalitz plot analysis KsPi+Pi- decay neutral D meson produced in B->D(*)K decays. The method exploits interference between D0 and D0bar to extract phi3, strong phase delta ratio r suppressed allowed amplitudes. apply this 605 fb-1 data sample collected by Belle experiment. uses three decays: B->DK, B->D*K with D*->DPi0 D*->Dgamma, as well corresponding charge-conjugate modes. From combined maximum likelihood fit modes, we...
The cross sections for ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}\ensuremath{\phi}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ and ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}\ensuremath{\phi}{f}_{0}(980)$ are measured from threshold to $\sqrt{s}=3.0\text{ }\text{ }\mathrm{GeV}$ using initial-state radiation. analysis is based on a data sample of $673\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ collected below the $\ensuremath{\Upsilon}(4S)$ resonance with Belle...
Using 605 fb−1 of data collected at the Υ(4S) resonance we present a measurement inclusive radiative B-meson decay channel, B→Xsγ. For lower photon energy thresholds 1.7, 1.8, 1.9, and 2.0 GeV, as defined in rest frame B meson, measure partial branching fraction mean variance spectrum. At 1.7 GeV threshold obtain BF(B→Xsγ)=(3.45±0.15±0.40)×10−4, where errors are statistical systematic.Received 8 July 2009DOI:https://doi.org/10.1103/PhysRevLett.103.241801©2009 American Physical Society
We demonstrate a single-parameter route for reproducing higher mass objects as observed in the LIGO--Virgo distribution, using only isolated binary stellar evolution channel. This single parameter encodes cosmological growth of compact remnants that exceed Tolman-Oppenheimer-Volkoff limit. Cosmological appears known solutions to General Relativity with boundary conditions. consider possibility conditions, which reduce Kerr on timescales short compared Hubble time. discuss complementary...
The effects of free radicals and hypotaurine on the development bovine embryos produced by in vitro fertilization vitro-matured oocytes were examined. Embryos that developed to 4- 6-cell stage after cultured without feeder cells TCM199 medium supplemented with 1% calf serum (CS) under either 5% CO2 air or O2, 90% N2. percentages blastocysts (including early, expanding, hatched stages) O2 was higher (P < .01) than percentage those 20% O2. T(d 8), 19% vs 6%; hathe respective concentration as...
We present a measurement of the decay B−→τ−ν¯τ using data sample containing 657×106 BB¯ pairs collected at Υ(4S) resonance with Belle detector KEKB asymmetric-energy e+e− collider. A B+B− are tagged by reconstructing one B+ meson decaying semileptonically. detect candidate in recoil. obtain signal significance 3.6 standard deviations including systematic uncertainties, and measure branching fraction to be B(B−→τ−ν¯τ)=[1.54−0.37+0.38(stat)−0.31+0.29(syst)]×10−4. This result confirms evidence...
We report measurements of the exclusive cross section for e+e−→D0D*−π+ as a function center-of-mass energy from D0D*−π+ threshold to 5.2 GeV with initial-state radiation. No evidence is found Y(4260)→D0D*−π+ decays. The analysis based on data sample collected Belle detector at or near 10.58 an integrated luminosity 695 fb−1 KEKB asymmetric-energy e+e− collider.Received 4 August 2009DOI:https://doi.org/10.1103/PhysRevD.80.091101©2009 American Physical Society
We measure the production cross sections for e+e- -> Upsilon(1S)pi+pi-, Upsilon(2S)pi+pi-, and Upsilon(3S)pi+pi- as a function of sqrt{s} between 10.83 GeV 11.02 GeV. The data consists 8.1 fb^-1 collected with Belle detector at KEKB collider. observe enhanced in all three final states that does not agree well conventional Upsilon(10860) lineshape. A fit using Breit-Wigner resonance shape yields peak mass [10888.4 +2.7/-2.6 (stat) +- 1.2 (syst)] MeV/c^2 width [30.7 +8.3/-7.0 3.1 MeV/c^2.
The differential cross section for the process $\ensuremath{\gamma}\ensuremath{\gamma}\ensuremath{\rightarrow}\ensuremath{\eta}{\ensuremath{\pi}}^{0}$ has been measured in kinematic range $0.84\text{ }\text{ }\mathrm{GeV}<W<4.0\text{ }\mathrm{GeV}$, $|\mathrm{cos}{\ensuremath{\theta}}^{*}|<0.8$, where $W$ and ${\ensuremath{\theta}}^{*}$ are energy ${\ensuremath{\pi}}^{0}$ (or $\ensuremath{\eta}$) scattering angle, respectively, $\ensuremath{\gamma}\ensuremath{\gamma}$ center-of-mass system....