T. Hirai

Tokyo Institute of Technology

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Trends

Author Order

Document Type

Co-Authors

G. N. Taylor

University of Melbourne

M. Tanaka

High Energy Accelerator Research Organization

K. Inami

Nagoya University

K. Tamai

University of Tsukuba

T. Tomura

The University of Tokyo

L. E. Piilonen

Virginia Tech

A. Ishikawa

High Energy Accelerator Research Organization

T. Sumiyoshi

Kyoto University

M. Hazumi

High Energy Accelerator Research Organization

F. Fang

California Institute of Technology

Cooperative Institutions

Laboratoire d’Annecy de Physique des Particules

578

Campbell Collaboration

402

Centre National de la Recherche Scientifique

359

European Organization for Nuclear Research

347

Budker Institute of Nuclear Physics

311

High Energy Accelerator Research Organization

307

Stanford University

294

SLAC National Accelerator Laboratory

284

Institut National de Physique Nucléaire et de Physique des Particules

256

University of Cincinnati

230

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Field

An Improved Measurement of Mixing-induced CP Violation in the Neutral B Meson System

arXiv (Cornell University) (2002)

Kazuo Abe Y. Chao S. Kobayashi S. Yanaka D. Liventsev

We present an improved measurement of the standard model CP violation parameter sin2phi_1 (also known as sin2beta) based on a sample of 85 times 10^6 B Bbar pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. One neutral B meson is reconstructed in a J/psi K_S, psi(2S) K_S, chi_{c1} K_S, eta_c K_S, J/psi K^{*0}, or J/psi K_L CP-eigenstate decay channel and the flavor of accompanying B meson is identified from itsdecay products. From the asymmetry in the distribution of the time intervals between the two B meson decay points, we obtain sin2phi_1 = 0.719 +/- 0.074(stat) +/- 0.035(syst). We also report measurements of CP violation parameters for the related B^0 -> J/psi pi^0 decay mode and the penguin-dominated processes B^0 -> eta' K_S, phi K_S and K^+K^- K_S.

B meson

CP violation

10.48550/arxiv.hep-ex/0207098

Cite

Citations (10)

Measurement ofBd0−B¯d0

Physical Review Letters (2001)

K. Abe K. Abe I. Adachi Byoung Sup Ahn H. Aihara

We report a determination of the B(0)(d)-&B_(0)(d) mixing parameter Deltam(d) based on the time evolution of dilepton yields in Upsilon(4S) decays. The measurement is based on a 5.9 fb(-1) data sample collected by the Belle detector at KEKB. The proper-time difference distributions for same-sign and opposite-sign dilepton events are simultaneously fitted to an expression containing Deltam(d) as a free parameter. Using both muons and electrons, we obtain Deltam(d) = 0.463+/-0.008 (stat)+/-0.016 (syst) ps(-1). This is the first determination of Deltam(d) from time evolution measurements at the Upsilon(4S). We also place limits on possible CPT violations.

KEKB

10.1103/physrevlett.86.3228

Cite

Citations (96)

Measurement of branching fractions for two-body B meson decays with charmonium at Belle

Kazuo Abe Y. Chao S. Kobayashi S. Yanaka Katsuhide Misono

Branching (polymer chemistry)

B meson

Branching fraction

Source

Cite

Citations (0)

Evidence for the Electroweak Penguin Decay $B \to X_{s}\ell^{+}\ell^{-}$}

arXiv (Cornell University) (2001)

Kazuo Abe Y. Chao S. Kobayashi S. Yanaka Katsuhide Misono

We report a search for the flavor-changing neutral current decay $B \to X_{s} \ell^{+} \ell^{-}$ using a 29.5 fb$^{-1}$ data sample accumulated at the $Υ(4S)$ resonance with the Belle detector at the KEKB $e^{+}e^{-}$ storage ring. We observe evidence for $B\to Kμ^+μ^-$ and report the preliminary branching fraction of ${\cal B}(B \to K μ^{+} μ^{-}) = (0.99^{+0.39}_{-0.32}^{+0.13}_{-0.15}) \times 10^{-6}$. We also set the following 90% confidence level upper limits on the branching fractions for exclusive and inclusive decays, ${\cal B}(B \to K e^{+} e^{-}) < 1.2 \times 10^{-6}$, ${\cal B}(B \to K^*(892) e^{+} e^{-}) < 5.1 \times 10^{-6}$, ${\cal B}(B \to K^*(892) μ^{+} μ^{-}) < 3.0 \times 10^{-6}$, ${\cal B}(B \to X_{s} e^{+} e^{-}) < 10.1 \times 10^{-6}$, ${\cal B}(B \to X_{s} μ^{+} μ^{-}) < 19.1 \times 10^{-6}$.

10.48550/arxiv.hep-ex/0107072

Cite

Citations (6)

A New 4 String Haptic Interface with 3DOF Presentation and 6DOF Measurement

The Proceedings of JSME annual Conference on Robotics and Mechatronics (Robomec) (2003)

Shoichi Hasegawa T. Hirai Munenori Inoue Makoto Sato

両手把持作業を行う場合, 3自由度力覚インタフェース2つを用いた場合片手では仮想物体の回転を入力できず, 両手でも, 両手を結ぶ軸回り回転を入力できない。しかし, 6自由度インタフェースを2つ組み合わせると, 機構の干渉のため可動域が狭くなってしまう。そこで, グリップを4本の糸で吊り, 4本の糸の長さに加えて糸の角度を計測することによって6自由度計測を行う力覚インタフェースを提案する。

Interface (matter)

Presentation (obstetrics)

10.1299/jsmermd.2003.49_5

Cite

Citations (0)

The Physics of the B Factories

The European Physical Journal C (2014)

A. J. Bevan B. Golob Th. Mannel S. Prell B. Yabsley

This work is on the Physics of the B Factories. Part A of this book contains a brief description of the SLAC and KEK B Factories as well as their detectors, BaBar and Belle, and data taking related issues. Part B discusses tools and methods used by the experiments in order to obtain results. The results themselves can be found in Part C. Please note that version 3 on the archive is the auxiliary version of the Physics of the B Factories book. This uses the notation alpha, beta, gamma for the angles of the Unitarity Triangle. The nominal version uses the notation phi_1, phi_2 and phi_3. Please cite this work as Eur. Phys. J. C74 (2014) 3026.

Unitarity

B-factory

BETA (programming language)

10.1140/epjc/s10052-014-3026-9

Cite

Citations (408)

Real-time luminosity monitor for a B-factory experiment

Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment (2001)

T. Hirai S. Uehara Yasushi Watanabe

Factory (object-oriented programming)

B-factory

Bhabha scattering

10.1016/s0168-9002(00)00766-x

Cite

Citations (12)

Observation of radiative B meson decays into higher kaonic resonances

Kazuo Abe Y. Chao S. Kobayashi S. Yanaka Katsuhide Misono

B meson

Source

Cite

Citations (2)

Studies Of Radiative B Meson Decays With Belle

A. Abashian Y. Kondo F. Handa Sidorov W. Ostrowicz

B meson

Source

Cite

Citations (2)

Observation of LargeCPViolation in the NeutralBMeson System

Physical Review Letters (2001)

K. Abe K. Abe R. Abe I. Adachi Byoung Sup Ahn

We present a measurement of the standard model $\mathrm{CP}$ violation parameter $\mathrm{sin}2{\ensuremath{\varphi}}_{1}$ based on a $29.1{\mathrm{fb}}^{\ensuremath{-}1}$ data sample collected at the $\ensuremath{\Upsilon}(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy ${e}^{+}{e}^{\ensuremath{-}}$ collider. One neutral $B$ meson is fully reconstructed as a $J/\ensuremath{\psi}{K}_{S}$, $\ensuremath{\psi}(2S){K}_{S}$, ${\ensuremath{\chi}}_{c1}{K}_{S}$, ${\ensuremath{\eta}}_{c}{K}_{S}$, $J/\ensuremath{\psi}{K}_{L}$, or $J/\ensuremath{\psi}{K}^{*0}$ decay and the flavor of the accompanying $B$ meson is identified from its decay products. From the asymmetry in the distribution of the time intervals between the two $B$ meson decay points, we determine $\mathrm{sin}2{\ensuremath{\varphi}}_{1}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0.99\ifmmode\pm\else\textpm\fi{}0.14(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.06(\mathrm{syst})$. We conclude that we have observed $\mathrm{CP}$ violation in the neutral $B$ meson system.

10.1103/physrevlett.87.091802

Cite

Citations (576)