- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- Dark Matter and Cosmic Phenomena
- Atomic and Subatomic Physics Research
- Neutrino Physics Research
- Particle Accelerators and Free-Electron Lasers
- School Choice and Performance
- Demographic Trends and Gender Preferences
- Particle Detector Development and Performance
- Family Dynamics and Relationships
- Gender, Labor, and Family Dynamics
- Poverty, Education, and Child Welfare
- Scientific Research and Discoveries
- COVID-19 Pandemic Impacts
- Cosmology and Gravitation Theories
- Black Holes and Theoretical Physics
- Astrophysics and Cosmic Phenomena
- Superconducting Materials and Applications
- Pulsars and Gravitational Waves Research
- Global Educational Reforms and Inequalities
- Computational Physics and Python Applications
- Vehicle emissions and performance
- Muon and positron interactions and applications
- Experimental Behavioral Economics Studies
Electronics and Telecommunications Research Institute
2014-2024
Institute for Basic Science
2015-2024
Seoul National University
2011-2024
University of California, Irvine
2024
University of Washington
2024
Seattle University
2023
Korea University of International Studies
2020-2023
RIKEN
2022
RIKEN Center for Quantum Computing
2022
Korea Advanced Institute of Science and Technology
2015-2022
The cross section for ee+ e- → π+ π- J/ψ between 3.8 and 5.5 GeV is measured with a 967 fb(-1) data sample collected by the Belle detector at or near Υ(nS) (n = 1,2,…,5) resonances. Y(4260) state observed, its resonance parameters are determined. In addition, an excess of production around 4 observed. This feature can be described Breit-Wigner parametrization properties that consistent Y(4008) was previously reported Belle. study decays, structure observed in M(π(±)J/ψ) mass spectrum 5.2σ...
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.
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...
An axion dark matter search with the CAPP-8TB haloscope is reported. Our results are sensitive to axion-photon coupling g_{aγγ} down QCD band over mass range between 6.62 and 6.82 μeV at a 90% confidence level, which most result in date.
The Center for Axion and Precision Physics Research at the Institute Basic Science is searching axion dark matter using ultralow temperature microwave resonators. We report exclusion of mass range $10.7126--10.7186\text{ }\text{ }\ensuremath{\mu}\mathrm{eV}$ with near Kim-Shifman-Vainshtein-Zakharov (KSVZ) coupling sensitivity $10.16--11.37\text{ about 9 times larger 90% confidence level. This first search result in these ranges. It also a resonator physical less than 40 mK.
We report an axion dark matter search at Dine-Fischler-Srednicki-Zhitnitskii sensitivity with the CAPP-12TB haloscope, assuming axions contribute 100% of local density. The excluded axion-photon coupling g_{aγγ} down to about 6.2×10^{-16} GeV^{-1} over mass range between 4.51 and 4.59 μeV a 90% confidence level. achieved experimental can also exclude Kim-Shifman-Vainshtein-Zakharov that makes up just 13% haloscope will continue wide masses.
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 perform a full amplitude analysis of B0→ψ′K+π− decays, with ψ′→μ+μ− or e+e−, to constrain the spin and parity Z(4430)−. The JP=1+ hypothesis is favored over 0−, 1−, 2− 2+ hypotheses at levels 3.4σ, 3.7σ, 4.7σ 5.1σ, respectively. based on 711 fb−1 data sample that contains 772×106 BB¯ pairs collected Υ(4S) resonance by Belle detector asymmetric-energy e+e− collider KEKB.7 MoreReceived 20 June 2013DOI:https://doi.org/10.1103/PhysRevD.88.074026© 2013 American Physical Society
We present results from a study of $X(3872)\ensuremath{\rightarrow}\ensuremath{\pi}\ensuremath{\pi}J/\ensuremath{\psi}$ decays produced via exclusive $B\ensuremath{\rightarrow}KX(3872)$ decays. determine the mass to be ${M}_{X(3872)}=(3871.85\ifmmode\pm\else\textpm\fi{}0.27(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.19(\mathrm{syst}))\text{ }\text{ }\mathrm{MeV}$, 90% confidence level upper limit on natural width ${\ensuremath{\Gamma}}_{X(3872)}<1.2\text{ product branching fraction...
We measure the branching fraction of B−→τ−¯ντ using full Υ(4S) data sample containing 772×106 B¯¯¯B pairs collected with Belle detector at KEKB asymmetric-energy e+e− collider. Events are tagged by reconstructing one B mesons decaying into hadronic final states, and candidates detected in recoil. find evidence for a significance 3.0 standard deviations including systematic errors B(B−→τ−¯ντ)=[0.72+0.27−0.25(stat)±0.11(syst)]×10−4.Received 16 November...
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 report the results of a search for charmonium-like state produced in process gamma --> omega J/psi 3.9-4.2 GeV/c^2 mass region. observe significant enhancement, which is well-described by resonant shape with M = (3915 +/- 3 2) MeV/c^2 and total width Gamma (17 10 3) MeV. This enhancement may be related to one or more three states so far reported 3.90-3.95
We report a study of $B\to (J/\psi \gamma) K$ and (\psi' \gamma)K$ decay modes using $772\times 10^{6}$ $B\bar{B}$ events collected at the \Upsilon(4S)$ resonance with Belle detector KEKB energy-asymmetric $e^+ e^-$ collider. observe $X(3872) \to J/\psi \gamma$ first evidence for $\chi_{c2} in (X_{c\bar{c}}\gamma) decays, while search \psi' no significant signal is found. measure branching fractions, $\mathcal{B}(B^{\pm} X(3872) K^{\pm}) \mathcal{B}(X(3872) J/\psi\gamma)$ $=$...
We report on a search for heavy neutrinos in B-meson decays. The results are obtained using data sample that contains 772x10^6 BB-bar pairs collected at the Upsilon(4S) resonance with Belle detector KEKB asymmetric-energy e+e- collider. No signal is observed and upper limits set mixing of left-handed Standard Model mass range 0.5 - 5.0 GeV/c^2.
We report the results of a study exclusive semileptonic decays B->pi0lnu, B->pi+lnu, B->rho0lnu, B->rho+lnu and B->omegalnu, where l represents an electron or muon. The events are tagged by fully reconstructing second B meson in event hadronic decay mode. measured branching fractions Br(B->pi0lnu) = (0.80 +- 0.08 0.04)x10^-4, Br(B->pi+lnu) (1.49 0.09 0.07)x10^-4, Br(B->rho0lnu) (1.83 0.10 0.10)x10^-4, Br(B->rho+lnu) (3.22 0.27 0.24)x10^-4, Br(B->omegalnu) =(1.07 0.16 first error is...
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 $(4350.6^{+4.6}_{-5.1}(\rm{stat})\pm 0.7(\rm{syst})) \hbox{MeV}/{\it c}^2$ $(13^{+18}_{-9}(\rm{stat})\pm 4(\rm{syst})) \hbox{MeV}$,...
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 a search for the rare decays $B\ensuremath{\rightarrow}{h}^{(*)}\ensuremath{\nu}\overline{\ensuremath{\nu}}$, where ${h}^{(*)}$ stands ${K}^{+}$, ${K}_{S}^{0}$, ${K}^{*+}$, ${K}^{*0}$, ${\ensuremath{\pi}}^{+}$, ${\ensuremath{\pi}}^{0}$, ${\ensuremath{\rho}}^{+}$, ${\ensuremath{\rho}}^{0}$ and $\ensuremath{\phi}$. The results are obtained from $711\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ data sample that contains $772\ifmmode\times\else\texttimes\fi{}{10}^{6}B\overline{B}$...
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:...
Efficient white-light-emitting diodes (WLEDs) have been developed using a polyfluorene-type blue-emitting conjugated polymer doped with green and red phosphorescent dyes. The emission spectrum of the polymer, which has very high luminescent efficiency, shows large spectral overlap absorbance iridium complexes. Also, efficient energy transfer from to complexes is observed. Poly(N-vinyl carbazole) used improve miscibility between because their poor chemical compatibility phase separation. A...
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...