A Ishikawa

High Energy Accelerator Research Organization, Tsukuba, Ibaraki, Japan

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Publications (947)

  • Source
    [Show abstract] [Hide abstract] ABSTRACT: A measurement of the cross section for the inclusive production of isolated prompt photons in proton-proton collisions at a centre-of-mass energy of \( \sqrt{s}=8 \) TeV is presented. The measurement covers the pseudorapidity ranges |η γ | < 1.37 and 1.56 ≤ |η γ | < 2.37 in the transverse energy range 25 < E T γ < 1500 GeV. The results are based on an integrated luminosity of 20.2 fb−1, recorded by the ATLAS detector at the LHC. Photon candidates are identified by combining information from the calorimeters and the inner tracker. The background is subtracted using a data-driven technique, based on the observed calorimeter shower-shape variables and the deposition of hadronic energy in a narrow cone around the photon candidate. The measured cross sections are compared with leading-order and next-to-leading order perturbative QCD calculations and are found to be in a good agreement over ten orders of magnitude.
    Full-text Article · Aug 2016 · Journal of High Energy Physics
  • [Show abstract] [Hide abstract] ABSTRACT: We report a measurement of the ratio ${\cal R}(D^*) = {\cal B}(\bar{B}^0 \rightarrow D^{*+} \tau^- \bar{\nu}_{\tau})/{\cal B}(\bar{B}^0 \rightarrow D^{*+} \ell^- \bar{\nu}_{\ell})$, where $\ell$ denotes an electron or a muon. The results are based on a data sample containing $772\times10^6$ $B\bar{B}$ pairs recorded at the $\Upsilon(4S)$ resonance with the Belle detector at the KEKB $e^+ e^-$ collider. We select a sample of $B^0 \bar{B}^0$ pairs by reconstructing both $B$ mesons in semileptonic decays to $D^{*\mp} \ell^{\pm}$. We measure ${\cal R}(D^*)= 0.302 \pm 0.030({\rm stat)} \pm 0.011({\rm syst)}$, which is within $1.6 \sigma$ of the Standard Model theoretical expectation, where the standard deviation $\sigma$ includes systematic uncertainties. We use this measurement to constrain several scenarios of new physics in a model-independent approach.
    Article · Jul 2016
  • [Show abstract] [Hide abstract] ABSTRACT: Using a data sample of 980 ${\rm fb}^{-1}$ of $e^+e^-$ annihilation data taken with the Belle detector operating at the KEKB asymmetric-energy $e^+e^-$ collider, we report the results of a study of excited $\Xi_c$ states that decay, via the emission of photons and/or charged pions, into $\Xi_c^0$ or $\Xi_c^+$ ground state charmed-strange baryons. We present new measurements of the masses of all members of the $\Xi_c^{\prime}$, $\Xi_c(2645)$, $\Xi_c(2790)$, $\Xi_c(2815)$, and $\Xi_c(2980)$ isodoublets, measurements of the intrinsic widths of those that decay strongly, and evidence of previously unknown transitions.
    Article · Jul 2016
  • [Show abstract] [Hide abstract] ABSTRACT: We report a measurement of the CP violation parameter $\varphi_1$ obtained in a time-dependent analysis of $B^0\to\overline{D}{}^{(*)0}h^0$ decays followed by $\overline{D}{}^0\to K_S^0\pi^+\pi^-$ decay. A model-independent measurement is performed using the binned Dalitz plot technique. The measured value is $\varphi_1 = 11.7^{\circ}\pm7.8^{\circ}({\rm stat.})\pm 2.1^{\circ}({\rm syst.})$. Treating $\sin{2\varphi_1}$ and $\cos{2\varphi_1}$ as independent parameters, we obtain $\sin{2\varphi_1} = 0.43\pm 0.27({\rm stat.})\pm 0.08({\rm syst.})$ and $\cos{2\varphi_1} = 1.06\pm 0.33({\rm stat.})^{+0.21}_{-0.15}({\rm syst.})$. The results are obtained with a full data sample of $772 \times 10^6 B\overline{B}$ pairs collected near the $\Upsilon(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider.
    Article · Jul 2016
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    [Show abstract] [Hide abstract] ABSTRACT: The process γγ→ppK+K- and its intermediate processes are measured for the first time using a 980 fb-1 data sample collected with the Belle detector at the KEKB asymmetric-energy e+e- collider. The production of ppK+K- and a Λ(1520)0 (Λ(1520)0) signal in the pK- (pK+) invariant mass spectrum are clearly observed. However, no evidence for an exotic baryon near 1540 MeV/c2, denoted as Θ(1540)0 (Θ(1540)0) or Θ(1540)++ (Θ(1540) - ), is seen in the pK- (pK+) or pK+ (pK-) invariant mass spectra. Cross sections for γγ→ppK+K-, Λ(1520)0pK++c.c. and the products σ(γγ→Θ(1540)0pK++c.c.)B(Θ(1540)0→pK-) and σ(γγ→Θ(1540)++pK-+c.c.)B(Θ(1540)++→pK+) are measured. We also determine upper limits on the products of the χc0 and χc2 two-photon decay widths and their branching fractions to ppK+K- at the 90% credibility level.
    Full-text Article · Jun 2016
  • [Show abstract] [Hide abstract] ABSTRACT: We report the first observation of the decay Λ_{c}^{+}→pK^{+}π^{-} using a 980 fb^{-1} data sample collected by the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. This is the first observation of a doubly Cabibbo-suppressed decay of a charmed baryon. We measure the branching ratio of this decay with respect to its Cabibbo-favored counterpart to be B(Λ_{c}^{+}→pK^{+}π^{-})/B(Λ_{c}^{+}→pK^{-}π^{+})=(2.35±0.27±0.21)×10^{-3}, where the uncertainties are statistical and systematic, respectively.
    Article · Jun 2016 · Physical Review Letters
  • [Show abstract] [Hide abstract] ABSTRACT: The branching fractions of the υ (1S) inclusive decays into final states with a J/ψ or a ψ(2S) are measured with improved precision to be B(υ (1S)→J/ψ+anything)=(5.25±0.13(stat)±0.25(syst))×10-4 and B(υ (1S)→ψ(2S)+anything)=(1.23±0.17(stat)±0.11(syst))×10-4. The first search for υ (1S) decays into XYZ states that decay into a J/ψ or a ψ(2S) plus one or two charged tracks yields no significant signals for XYZ states in any of the examined decay modes, and upper limits on their production rates in υ (1S) inclusive decays are determined.
    Article · Jun 2016
  • [Show abstract] [Hide abstract] ABSTRACT: We have searched for the decay B-0 -> phi gamma sing the full Belle data set of 772 x 10(6) B (B) over bar pairs collected at the gamma(4S) resonance with the Belle detector at the KEKB e(+)e(-) collider. No signal is observed, and we set an upper limit on the branching fraction of B(B-0 -> phi gamma) < 1.0 x 10(-7) at the 90% confidence level. This is the most stringent limit on this decay mode to date.
    Article · Jun 2016
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    [Show abstract] [Hide abstract] ABSTRACT: We report a study of radiative decays of \chi_{bJ}(1P)(J=0,1,2) mesons into 74 hadronic final states comprising charged and neutral pions, kaons, protons; out of these, 41 modes are observed with at least 5 standard deviation significance. Our measurements not only improve the previous measurements by the CLEO Collaboration but also lead to first observations in many new modes. The large sample allows us to probe the total decay width of the \chi_{b0}(1P). In the absence of a statistically significant result, a 90% confidence-level upper limit is set on the width at \Gamma_{total}< 2.4 MeV. Our results are based on 24.7 fb^{-1} of e+e- collision data recorded by the Belle detector at the \Upsilon(2S) resonance, corresponding to (157.8\pm3.6)\times10^6 \Upsilon(2S) decays.
    Full-text Article · Jun 2016
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    Y. Kato · T. Iijima · I. Adachi · [...] · A. Zupanc
    [Show abstract] [Hide abstract] ABSTRACT: We report the discovery of $\Xi_{c}(3055)^{0}$, observed by its decay into the final state $\Lambda D^{0}$, and present the first observation and evidence of the decays of $\Xi_c(3055)^{+}$ and $\Xi_c(3080)^{+}$ into $\Lambda D^{+}$. We also perform a combined analysis of the $\Lambda D^{+}$ with the $\Sigma_{c}^{++}K^{-}$ and $\Sigma_{c}^{\ast ++}K^{-}$ decay modes to measure the ratios of branching fractions, masses and widths with improved accuracy. We measure the ratios of branching fractions ${\cal B}(\Xi_{c}(3055)^{+} \to \Lambda D^{+})/{\cal B}(\Xi_{c}(3055)^{+} \to \Sigma_{c}^{++}K^{-})=5.09\pm1.01\pm0.76$, ${\cal B}(\Xi_{c}(3080)^{+} \to \Lambda D^{+})/{\cal B}(\Xi_{c}(3080)^{+} \to \Sigma_{c}^{++}K^{-})=1.29\pm0.30\pm0.15$, and ${\cal B}(\Xi_{c}(3080)^{+} \to \Sigma_{c}^{\ast ++}K^{-})/{\cal B}(\Xi_{c}(3080)^{+} \to \Sigma_{c}^{++}K^{-})=1.07\pm0.27\pm0.01$, where the uncertainties are statistical and systematic. The analysis is performed using a 980 fb$^{-1}$ data sample collected with the Belle detector at the KEKB asymmetric-energy $e^{+}e^{-}$ collider.
    Full-text Article · May 2016
  • [Show abstract] [Hide abstract] ABSTRACT: We report the analysis of the three-body e^{+}e^{-}→BB[over ¯]π^{±}, BB[over ¯]^{*}π^{±}, and B^{*}B[over ¯]^{*}π^{±} processes, including the first observations of the Z_{b}^{±}(10610)→[BB[over ¯]^{*}+c.c.]^{±} and Z_{b}^{±}(10650)→[B^{*}B[over ¯]^{*}]^{±} transitions that are found to dominate the corresponding final states. We measure Born cross sections for the three-body production of σ(e^{+}e^{-}→[BB[over ¯]^{*}+c.c.]^{±}π^{∓})=[17.4±1.6(stat)±1.9(syst)] pb and σ(e^{+}e^{-}→[B^{*}B[over ¯]^{*}]^{±}π^{∓})=[8.75±1.15(stat)±1.04(syst)] pb and set a 90% C.L. upper limit of σ(e^{+}e^{-}→[BB[over ¯]]^{±}π^{∓})<2.9 pb. The results are based on a 121.4 fb^{-1} data sample collected with the Belle detector at a center-of-mass energy near the ϒ(10860) peak.
    Article · May 2016 · Physical Review Letters
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    [Show abstract] [Hide abstract] ABSTRACT: We present a search for a non-Standard-Model invisible particle $X^0$ in the mass range $0.1\textrm{-}1.8 \,{\rm GeV}/{c^2}$ in $B^{+}\to e^{+} X^{0}$ and $B^{+}\to \mu^{+} X^{0}$ decays. The results are obtained from a $711~{\rm fb}^{-1}$ data sample that corresponds to $772 \times 10^{6} B\bar{B}$ pairs, collected at the $\Upsilon(4S)$ resonance with the Belle detector at the KEKB $e^+ e^-$ collider. One $B$ meson is fully reconstructed in a hadronic mode to determine the momentum of the lepton of the signal decay in the rest frame of the recoiling partner $B$ meson. We find no evidence of a signal and set upper limits on the order of $10^{-6}$.
    Full-text Article · May 2016
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    [Show abstract] [Hide abstract] ABSTRACT: The branching fractions of the $\Upsilon(1S)$ inclusive decays into final states with a $J/\psi$ or a $\psi(2S)$ are measured with improved precision to be $\BR(\Upsilon(1S)\to J/\psi + {\rm anything})=(5.25\pm 0.13(\mathrm{stat.})\pm 0.25(\mathrm{syst.}))\times 10^{-4}$ and $\BR(\Upsilon(1S)\to \psi(2S) + {\rm anything})=(1.23\pm 0.17(\mathrm{stat.})\pm 0.11(\mathrm{syst.}))\times 10^{-4}$. The first search for $\Upsilon(1S)$ decays into $XYZ$ states that decay into a $J/\psi$ or a $\psi(2S)$ plus one or two charged tracks yields no significant signals for $XYZ$ states in any of the examined decay modes, and upper limits on their production rates in $\Upsilon(1S)$ inclusive decays are determined.
    Full-text Article · May 2016
  • [Show abstract] [Hide abstract] ABSTRACT: We measure the decay Bs0→K0K0 using data collected at the ?(5S) resonance with the Belle detector at the KEKB e+e- collider. The data sample used corresponds to an integrated luminosity of 121.4 fb-1. We measure a branching fraction B(Bs0→K0K0)=[19.6-5.1+5.8(stat)±1.0(syst)±2.0(NBs0Bs0)]×10-6 with a significance of 5.1 standard deviations. This measurement constitutes the first observation of this decay.
    Article · Apr 2016 · Physical Review Letters
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    [Show abstract] [Hide abstract] ABSTRACT: We present a measurement of angular observables, $P_4'$, $P_5'$, $P_6'$, $P_8'$, in the decay $B^0 \to K^\ast(892)^0 \ell^+ \ell^-$, where $\ell^+\ell^-$ is either $e^+e^-$ or $\mu^+\mu^-$. The analysis is performed on a data sample corresponding to an integrated luminosity of $711~\mathrm{fb}^{-1}$ containing $772\times 10^{6}$ $B\bar B$ pairs, collected at the $\Upsilon(4S)$ resonance with the Belle detector at the asymmetric-energy $e^+e^-$ collider KEKB. Four angular observables, $P_{4,5,6,8}'$ are extracted in five bins of the invariant mass squared of the lepton system, $q^2$. We compare our results for $P_{4,5,6,8}'$ with Standard Model predictions including the $q^2$ region in which the LHCb collaboration reported the so-called $P_5'$ anomaly.
    Full-text Article · Apr 2016
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    [Show abstract] [Hide abstract] ABSTRACT: The process $\gamma \gamma \to p \bar{p} K^+ K^-$ and its intermediate processes are measured for the first time using a 980~fb$^{-1}$ data sample collected with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider. The production of $p \bar{p} K^+ K^-$ and a $\Lambda(1520)^0~(\bar{\Lambda}(1520)^0)$ signal in the $pK^-$~($\bar{p} K^+$) invariant mass spectrum are clearly observed. However, no evidence for an exotic baryon near 1540~MeV/$c^2$, denoted as $\Theta(1540)^0$~($\bar{\Theta}~(1540)^0$) or $\Theta(1540)^{++}$~($\Theta(1540)^{--}$), is seen in the $p K^-$~($\bar{p}K^+$) or $pK^+$~($\bar{p} K^-$) invariant mass spectra. Cross sections for $\gamma \gamma \to p \bar{p} K^+ K^-$, $\Lambda(1520)^0 \bar{p} K^+ +c.c.$ and the products $\sigma(\gamma \gamma \to \Theta(1540)^0 \bar{p} K^+ +c.c.)\BR(\Theta(1540)^0 \to p K^{-})$ and $\sigma(\gamma \gamma \to \Theta(1540)^{++} \bar{p} K^- +c.c.)\BR(\Theta(1540)^{++}\to p K^{+})$ are measured. We also determine upper limits on the products of the $\chi_{c0}$ and $\chi_{c2}$ two-photon decay widths and their branching fractions to $p \bar{p} K^+ K^-$ at the 90\% credibility level.
    Full-text Article · Apr 2016
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    A. Ishikawa · H. Yamamoto · A. Abdesselam · [...] · A. Zupanc
    [Show abstract] [Hide abstract] ABSTRACT: We report a measurement of the amplitude ratio $r_S$ of $B^0 \to D^0K^{\ast 0}$ and $B^0 \to \bar {D^0}K^{\ast 0}$ decays with a Dalitz analysis of $D\to K_S^0\pi ^+\pi ^-$ decays, for the first time using a model-independent method. We set an upper limit $r_S < 0.87$ at the 68% confidence level, using the full data sample of $711\,{\rm fb}^{-1}$ corresponding to $772\times 10^6$ $B\bar {B}$ pairs collected at the $\Upsilon (4S)$ resonance with the Belle detector at the KEKB $e^+e^-$ collider. This result is obtained from observables $x_- = +0.4 ^{+1.0 +0.0}_{-0.6 -0.1} \pm 0.0$, $y_- = -0.6 ^{+0.8 +0.1}_{-1.0 -0.0} \pm 0.1$, $x_+ = +0.1 ^{+0.7 +0.0}_{-0.4 -0.1} \pm 0.1$, and $y_+ = +0.3 ^{+0.5 +0.0}_{-0.8 -0.1} \pm 0.1$, where $x_\pm = r_S \cos (\delta _S \pm \phi _3)$, $y_\pm = r_S \sin (\delta _S \pm \phi _3)$, and $\phi _3\ (\delta _S)$ is the weak (strong) phase difference between $B^0 \to D^0K^{\ast 0}$ and $B^0 \to \bar {D^0}K^{\ast 0}$.
    Full-text Article · Apr 2016 · Progress of Theoretical and Experimental Physics
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    [Show abstract] [Hide abstract] ABSTRACT: We report inclusive and exclusive measurements for $\chi_{c1}$ and $\chi_{c2}$ production in $B$ decays. We measure $\mathcal{B}(B \to \chi_{c1} X)$= $(3.03 \pm 0.05(\mbox{stat}) \pm 0.24(\mbox{syst})) \times 10^{-3}$ and $\mathcal{B}(B \to \chi_{c2} X)$= $(0.70 \pm 0.06(\mbox{stat}) \pm 0.10(\mbox{syst})) \times 10^{-3}$. For the first time, $\chi_{c2}$ production in exclusive $B$ decays in the modes $B^0 \to \chi_{c2}\pi^- K^+$ and $B^+ \to \chi_{c2} \pi^+ \pi^- K^+$ has been observed, along with first evidence for the $B^+ \to \chi_{c2} \pi^+ K_S^0$ decay mode. For $\chi_{c1}$ production, we report the first observation in the $B^+ \to \chi_{c1} \pi^+ \pi^- K^+$, $B^0 \to \chi_{c1} \pi^+ \pi^- K_S^0$ and $B^0 \to \chi_{c1} \pi^0 \pi^- K^+$ decay modes. Using these decay modes, we observe a difference in the production mechanism of $\chi_{c2}$ in comparison to $\chi_{c1}$ in $B$ decays. In addition, we report searches for $X(3872)$ and $\chi_{c1}(2P)$ in the $B^+ \to (\chi_{c1} \pi^+ \pi^-) K^+$ decay mode. The reported results use $772 \times 10^{6}$ $B\overline{B}$ events collected at the $\Upsilon(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider.
    Full-text Article · Mar 2016 · Physical Review D
  • [Show abstract] [Hide abstract] ABSTRACT: We report inclusive and exclusive measurements for χc1 and χc2 production in B decays. We measure B(B→χc1X)=(3.03±0.05(stat)±0.24(syst))×10-3 and B(B→χc2X)=(0.70±0.06(stat)±0.10(syst))×10-3. For the first time, χc2 production in exclusive B decays in the modes B0→χc2π-K+ and B+→χc2π+π-K+ has been observed, along with first evidence for the B+→χc2π+KS0 decay mode. For χc1 production, we report the first observation in the B+→χc1π+π-K+, B0→χc1π+π-KS0 and B0→χc1π0π-K+ decay modes. Using these decay modes, we observe a difference in the production mechanism of χc2 in comparison to χc1 in B decays. In addition, we report searches for X(3872) and χc1(2P) in the B+→(χc1π+π-)K+ decay mode. The reported results use 772×106 BB-events collected at the (4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider.
    Article · Mar 2016
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    [Show abstract] [Hide abstract] ABSTRACT: We report a measurement of ratio ${\cal R}(D^*) = {\cal B}(\bar{B}^0 \rightarrow D^{*+} \tau^- \bar{\nu}_{\tau})/{\cal B}(\bar{B}^0 \rightarrow D^{*+} \ell^- \bar{\nu}_{\ell})$, where $\ell$ denotes an electron or a muon. The results are based on a data sample containing $772\times10^6$ $B\bar{B}$ pairs recorded at the $\Upsilon(4S)$ resonance with the Belle detector at the KEKB $e^+ e^-$ collider. We select a sample of $B^0 \bar{B}^0$ pairs by reconstructing both $B$ mesons in semileptonic decays to $D^{*\mp} \ell^{\pm}$. We measure ${\cal R}(D^*)= 0.302 \pm 0.030({\rm stat)} \pm 0.011({\rm syst)}$, which is within $1.6 \sigma$ of the Standard Model theoretical expectation, where $\sigma$ is the standard deviation including systematic uncertainties.
    Full-text Article · Mar 2016

Publication Stats

14k Citations

Institutions

  • 2013
    • High Energy Accelerator Research Organization
      • Institute of Particle and Nuclear Studies
      Tsukuba, Ibaraki, Japan
    • Toho University
      Edo, Tokyo, Japan
    • University of Illinois, Urbana-Champaign
      Urbana, Illinois, United States
    • Nara Women's University
      Nara, Nara, Japan
  • 2006-2013
    • Tata Institute of Fundamental Research
      • Department of Biological Sciences
      Mumbai, Mahārāshtra, India
    • Virginia Polytechnic Institute and State University
      • Department of Chemical Engineering
      Blacksburg, Virginia, United States
  • 2003-2013
    • Seoul National University
      • Department of Physics and Astronomy
      Sŏul, Seoul, South Korea
  • 2012
    • Novosibirsk State University
      Novo-Nikolaevsk, Novosibirsk, Russia
  • 2011-2012
    • University of Seoul
      Sŏul, Seoul, South Korea
    • Panjab University
      Chandigarh, Chandīgarh, India
  • 2010-2012
    • University of Freiburg
      • Faculty of Mathematics and Physics
      Freiburg, Lower Saxony, Germany
  • 2002-2012
    • Tohoku Gakuin University
      Japan
    • National Taiwan University
      • Department of Physics
      Taipei, Taipei, Taiwan
    • Gyeongsang National University
      Shinshū, South Gyeongsang, South Korea
  • 2007-2011
    • Saga University
      • Department of Mechanical Engineering
      Сага Япония, Saga, Japan
    • Fu Jen Catholic University
      • Department of Physics
      Taipei, Taipei, Taiwan
    • Institute of Nuclear Physics
      Cracovia, Lesser Poland Voivodeship, Poland
    • Institute of High Energy Physics
      Protvino, Moskovskaya, Russia
    • Kanagawa University
      Yokohama, Kanagawa, Japan
  • 2004-2011
    • Tohoku University
      • Research Center for Electron Photon Science
      Sendai, Kagoshima-ken, Japan
    • Victoria University Melbourne
      Melbourne, Victoria, Australia
  • 2009
    • Kobe University
      • Graduate School of Science
      Kōbe, Hyōgo, Japan
  • 2005-2009
    • École Polytechnique Fédérale de Lausanne
      Lausanne, Vaud, Switzerland
    • Peking University
      • School of Electronics Engineering and Computer Science
      Peping, Beijing, China
  • 2008
    • Justus-Liebig-Universität Gießen
      Gieben, Hesse, Germany
    • The Graduate University for Advanced Studies
      Миура, Kanagawa, Japan
    • Princeton University
      Princeton, New Jersey, United States
  • 2004-2008
    • Institut für Hochenergiephysik Wien
      Wien, Vienna, Austria
    • Institute for Theoretical and Experimental Physics
      Moskva, Moscow, Russia
  • 2002-2008
    • Budker Institute of Nuclear Physics
      Novo-Nikolaevsk, Novosibirsk, Russia
  • 2006-2007
    • Hefei University of Technology
      Luchow, Anhui Sheng, China
  • 2005-2007
    • University of Cincinnati
      • Department of Physics
      Cincinnati, Ohio, United States
    • Jožef Stefan Institute
      Lubliano, Ljubljana, Slovenia
  • 2000-2006
    • Nagoya University
      • Graduate School of Science
      Nagoya-shi, Aichi-ken, Japan
    • Kashiwa Kousei General Hospital
      Kashiwa, Chiba, Japan
  • 2001-2005
    • Aomori University
      Aomori, Aomori Prefecture, Japan
  • 2002-2003
    • University of Lausanne
      Lausanne, Vaud, Switzerland
  • 2001-2002
    • Chuo University
      Edo, Tōkyō, Japan
  • 1999-2002
    • Hokkaido University
      • Division of Physics
      Sapporo, Hokkaidō, Japan
    • Himeji Institute of Technology
      • Department of Material Science
      Himezi, Hyōgo, Japan