H. Nakazawa
A5102823498- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- Particle Detector Development and Performance
- Computational Physics and Python Applications
- Particle Accelerators and Free-Electron Lasers
- Dark Matter and Cosmic Phenomena
- Crystallography and molecular interactions
- Neutrino Physics Research
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Black Holes and Theoretical Physics
- Superconducting Materials and Applications
- Medical Imaging Techniques and Applications
- Atomic and Subatomic Physics Research
- Radiation Detection and Scintillator Technologies
- Astrophysics and Cosmic Phenomena
- Advanced Data Storage Technologies
- Origins and Evolution of Life
- Molecular spectroscopy and chirality
- Complex Systems and Time Series Analysis
- Cosmology and Gravitation Theories
- Organometallic Complex Synthesis and Catalysis
- Epoxy Resin Curing Processes
- Muon and positron interactions and applications
National Taiwan University
2016-2022
National Central University
2007-2016
Nara Women's University
2014
Osaka City University
2004-2006
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...
We present measurements of B+→¯¯¯D*0τ+ντ and B+→¯¯¯D0τ+ντ decays in a data sample 657×106 B¯¯¯B pairs collected with the Belle detector at KEKB asymmetric-energy e+e− collider. find 446+58−56 events significance 8.1 standard deviations, 146+42−41 3.5 deviations. The latter signal provides first evidence for this decay mode. measured branching fractions are B(B+→¯¯¯D*0τ+ντ)=(2.12+0.28−0.27(stat)±0.29(syst))% B(B+→¯¯¯D0τ+ντ)=(0.77±0.22(stat)±0.12(syst))%.Received 13 May...
We report results of a study doubly charmed baryons and strange baryons. The analysis is performed using $980\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ data sample collected with the Belle detector at KEKB asymmetric-energy ${e}^{+}{e}^{\ensuremath{-}}$ collider. search for ${\mathrm{\ensuremath{\Xi}}}_{cc}^{+(+)}$ ${\mathrm{\ensuremath{\Lambda}}}_{c}^{+}{K}^{\ensuremath{-}}{\ensuremath{\pi}}^{+}({\ensuremath{\pi}}^{+})$...
We report measurements of branching fractions $\tau$ lepton decays to final states with a $K^{0}_{S}$ meson using 669 fb$^{-1}$ data sample accumulated the Belle detector at KEKB asymmetric-energy $e^{+}e^{-}$ collider. The inclusive fraction is measured be $\mathcal{B}(\tau^{-} \to K^{0}_{S}\ X^{-} \nu_{\tau})=(9.15 \pm 0.01 0.15) \times 10^{-3}$, where $X^{-}$ can anything; exclusive are \pi^{-} K^{0}_{S} \nu_{\tau}) = (4.16 0.08) K^{-} (7.40 0.07 0.27) 10^{-4}$, \pi^{0} (1.93 0.02 0.07)...
We report a measurement of the differential cross section ${\ensuremath{\pi}}^{0}$ pair production in single-tag two-photon collisions, ${\ensuremath{\gamma}}^{*}\ensuremath{\gamma}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{0}{\ensuremath{\pi}}^{0}$, ${e}^{+}{e}^{\ensuremath{-}}$ scattering. The is measured for ${Q}^{2}$ up to $30\text{ }\text{ }{\mathrm{GeV}}^{2}$, where negative invariant mass squared tagged photon, kinematic range $0.5\text{ }\mathrm{GeV}<W<2.1\text{ }\mathrm{GeV}$ and...
The suppressed decay chain B(-)→DK(-), D→K(+)π(-), where D indicates a D(¯)(0) or D(0) state, provides important information on the CP-violating angle ϕ(3). We measure ratio R(DK) of rates to favored mode D→K(-)π(+) be R(DK)=[1.63(-0.41)(+0.44)(stat)(-0.13)(+0.07)(syst)]×10(-2), which first evidence signal with significance 4.1σ. also asymmetry A(DK) between charge-conjugate decays A(DK)=-0.39(-0.28)(+0.26)(stat)(-0.03)(+0.04)(syst). results are based full 772×10(6) BB(¯) pair data sample...
The $e^+e^- \to \pi^+ \pi^- \pi^0 \chi_{bJ}$ ($J=0,~1,~2$) processes are studied using a 118~fb$^{-1}$ data sample collected at center-of-mass energy of 10.867 GeV, in the $\Upsilon(10860)$ range, with Belle detector. $\pi^+ \chi_{b1}$, $\pi^+\pi^-\pi^0\chi_{b2}$, $\omega\chi_{b1}$ signals and evidence $\omega\chi_{b2}$ observed for first time cross sections measured. No significant $\pi^+\pi^-\pi^0\chi_{b0}$ or $\omega\chi_{b0}$ signal is 90\% confidence level upper limits on these two...
We report a high-statistics measurement of the differential cross section process |$\gamma \gamma \to K^0_S K^0_S$| in range |$1.05\,{\mathrm {GeV}} \leq W 4.00$| GeV, where is center-of-mass energy colliding photons, using 972 fb|$^{-1}$| data collected with Belle detector at KEKB asymmetric-energy |$e^+ e^-$| collider operated and near |$\Upsilon $|-resonance region. The fitted by parameterized S-, D|$_0$|-, D|$_2$|-, G|$_0$|-, G|$_2$|-wave amplitudes. In D|$_2$| wave, |$f_2(1270)$|,...
We measure the branching fractions of ${B}^{0}\ensuremath{\rightarrow}J/\ensuremath{\psi}{\ensuremath{\eta}}^{(\ensuremath{'})}$ decays with complete Belle data sample $772\ifmmode\times\else\texttimes\fi{}{10}^{6}$ $B\overline{B}$ events collected at $\ensuremath{\Upsilon}(4S)$ resonance detector KEKB asymmetric-energy ${e}^{+}{e}^{\ensuremath{-}}$ collider. The results for are:...
We report the result from first search for $D^0$ decays to invisible final states. The analysis is performed on a data sample of 924 $\rm{fb}^{-1}$ collected at and near $\Upsilon(4S)$ $\Upsilon(5S)$ resonances with Belle detector KEKB asymmetric-energy $e^{+}e^{-}$ collider. absolute branching fraction determined using an inclusive sample, obtained by fully reconstructing rest particle system including other charmed particle. No significant signal yield observed upper limit $9.4\times...
The invariant mass spectrum of the ${\ensuremath{\eta}}^{\ensuremath{'}}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ final state produced in two-photon collisions is obtained using a $673\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ data sample collected vicinity $\ensuremath{\Upsilon}(4S)$ resonance with Belle detector at KEKB asymmetric-energy ${e}^{+}{e}^{\ensuremath{-}}$ collider. We observe clear signal ${\ensuremath{\eta}}_{c}(1S)$ and measure its width to be...
We report an observation of the |$B^{\pm } \to J/\psi \eta K^{\pm }$| and |$B^0 K^0_S$| decays using |$772\times 10^{6}B\overline {B}$| pairs collected at |$\Upsilon (4S)$| resonance with Belle detector KEKB asymmetric-energy |$e^+e^-$| collider. obtain branching fractions |${\mathcal B}(B^{\pm }\rightarrow })=(1.27\pm 0.11(\hbox {stat.})\pm {syst.}))\times 10^{-4}$| B}(B^0\to K^0_S)=(5.22 \pm 0.78 (\hbox {stat.}) 0.49 10^{-5}$|. search for a new narrow charmonium(-like) state |$X$| in...
We report a measurement of the time-integrated $CP$ asymmetry in neutral charm meson decay $D^0 \to K^0_S K^0_S$ using 921~fb$^{-1}$ data collected at $Υ(4S)$ and $Υ(5S)$ resonances with Belle detector KEKB asymmetric-energy $e^+e^-$ collider. The observed is $$ A_{CP}(D^0 K^0_S) = (-0.02 \pm 1.53 0.17) \%, where first uncertainty statistical second systematic. This latter dominated by error normalisation channel. result consistent Standard Model expectations improves respect to previous...
Using a sample of 158 million \Upsilon(2S) events collected with the Belle detector, charmonium and charmonium-like states even charge parity are searched for in radiative decays. No significant \chi_{cJ} or \eta_c signal is observed following upper limits at 90% confidence level (C.L.) obtained: BR(\Upsilon(2S)\to \gamma \chi_{c0})< 1.0 \times 10^{-4}, BR(\Upsilon(2S) \to \chi_{c1})<3.6 10^{-6}, \chi_{c2})<1.5 10^{-5}, \eta_c)< 2.7 10^{-5}. any state observed, we obtain \BR(\Upsilon(2S)\to...
We present an extraction of azimuthal correlations between two pairs charged pions detected in opposite jets from electron-positron annihilation. These may arise the dependence di-pion fragmentation on polarization parent quark process $e^+e^- \rightarrow q \bar{q}$. Due to correlation polarizations, cross-section pair production, which pion are a dijet event, exhibits modulation angles planes containing hadron with respect production plane. The measurement this allows access combinations...
We have searched for the decay ${B}^{0}\ensuremath{\rightarrow}\ensuremath{\phi}\ensuremath{\gamma}$ using full Belle data set of $772\ifmmode\times\else\texttimes\fi{}{10}^{6}$ $B\overline{B}$ pairs collected at $\mathrm{\ensuremath{\Upsilon}}(4\text{S})$ resonance with detector KEKB ${e}^{+}{e}^{\ensuremath{-}}$ collider. No signal is observed, and we an upper limit on branching fraction...
We report a search for dark vector gauge boson ${U}^{\ensuremath{'}}$ that couples to quarks in the decay chain ${D}^{*+}\ensuremath{\rightarrow}{D}^{0}{\ensuremath{\pi}}^{+},{D}^{0}\ensuremath{\rightarrow}{K}_{S}^{0}\ensuremath{\eta},\ensuremath{\eta}\ensuremath{\rightarrow}{U}^{\ensuremath{'}}\ensuremath{\gamma}$, ${U}^{\ensuremath{'}}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$. No signal is found and we set mass-dependent limit on baryonic fine...
Abstract We report the stereocontrol of diene polymers by topochemical polymerization alkoxy‐substituted benzyl muconates in solid state. A monomer stacking structure is controlled weak intermolecular interactions crystals, depending on and position alkoxy‐substituent. The translational alternating types molecular structures a column provide diisotactic disyndiotactic polymers, respectively, solid‐state under UV γ‐ray irradiation. On other hand, meso racemo resulting are determined symmetry...
We describe here the novel phase transition of organic polymer crystals that are directly fabricated by topochemical polymerization 4-bromo- and 4-chlorobenzyl esters (Z,Z)-muconic acid as 1,3-diene monomers in crystalline state. The obtained polymers thermally stable, their crystal structures reversibly change two steps according to temperature. has been revealed on basis results thermal analyses including thermogravimetric analysis (TG), differential (DTA), scanning calorimetry (DSC), well...
We report results on the studies of $e^+e^-\to B_s^{(*)}\bar{B}_s^{(*)}$ processes. The are based a $121.4$ fb$^{-1}$ data sample collected with Belle detector at center-of-mass energy near $Υ(10860)$ peak and $16.4$ 19 points in range from 10.77 to 11.02 GeV. observe clear $e^+e^-\toΥ(10860)\to signal, no statistically significant signal Υ(11020)\to B_s^{(*)}\bar{B}_s^{(*)}$. relative production ratio $B_s^*\bar{B}_s^*$, $B_s\bar{B}_s^{*}$, $B_s\bar{B}_s$ final states $\sqrt{s}=10.866$ GeV...
We search for the charmless ${B}^{0}$ decay with final state particles $p\overline{\mathrm{\ensuremath{\Lambda}}}{\ensuremath{\pi}}^{\ensuremath{-}}\ensuremath{\gamma}$ using full data sample that contains $772\ifmmode\times\else\texttimes\fi{}1{0}^{6}B\overline{B}$ pairs collected at $\mathrm{\ensuremath{\Upsilon}}(4S)$ resonance Belle detector KEKB asymmetric-energy ${e}^{+}{e}^{\ensuremath{-}}$ collider. This is predicted to proceed predominantly via...
The Level-1 trigger system (TRG) in the Belle II experiment is designed to summarize real-time sub-detectors information by using FPGA chips for central data acquisition (DAQ) system, and it includes several sub-trigger systems triggering various types of physics events interest. main focus this report CDCTRG: track with Central Drift Chamber (CDC) detector, which responsible trajectory reconstruction charged particles algorithms: Track-Segment Finder, 2D, 3D, Neuro-3D, short tracking....