D. Anipko

Publications (133)180.83 Total impact

• Article: New search for τ→μγ and τ→eγ decays at Belle

  Belle Collaboration, K. Hayasaka, K. Abe, I. Adachi, H. Aihara, D. Anipko, K. Arinstein, V. Aulchenko, A. M. Bakich, E. Barberio, [......], E. Won, Q. L. Xie, B. D. Yabsley, A. Yamaguchi, Y. Yamashita, M. Yamauchi, Z. P. Zhang, V. Zhilich, V. Zhulanov, A. Zupanc
  [show abstract] [hide abstract]
  ABSTRACT: We report on a search for the lepton flavor violating τ→μγ and τ→eγ decays based on 535 fb-1 of data accumulated at the Belle experiment. No signal is found and we set 90% confidence level upper limits on the branching ratios B(τ→μγ)<4.5×10 and B(τ→eγ)<1.2×10.
  Physics Letters B 07/2008; 666:16-22. · 3.95 Impact Factor
• Article: Measurement of Einstein-Podolsky-Rosen-type flavor entanglement in Upsilon(4S) --> B0 B0 decays.

  A Go, A Bay, K Abe, H Aihara, D Anipko, V Aulchenko, T Aushev, A M Bakich, E Barberio, K Belous, [......], J Wicht, E Won, Q L Xie, B D Yabsley, A Yamaguchi, Y Yamashita, M Yamauchi, Z P Zhang, V Zhilich, A Zupanc
  [show abstract] [hide abstract]
  ABSTRACT: The neutral B meson pair produced at the Upsilon(4S) should exhibit a nonlocal correlation of the type discussed by Einstein, Podolsky, and Rosen. We measure this correlation using the time-dependent flavor asymmetry of semileptonic B(0) decays, which we compare with predictions from quantum mechanics and two local realistic models. The data are consistent with quantum mechanics, and inconsistent with the other models. Assuming that some B pairs disentangle to produce B(0) and B(0) with definite flavor, we find a decoherent fraction of 0.029 +/ -0.057, consistent with no decoherence.
  Physical Review Letters 10/2007; 99(13):131802. · 7.37 Impact Factor
• Article: Study of B+→pΛ̅ γ, pΛ̅ π0 and B0→pΛ̅ π-

  M.-Z. Wang, Y.-J. Lee, K. Abe, I. Adachi, H. Aihara, D. Anipko, T. Aushev, S. Bahinipati, A. M. Bakich, I. Bedny, [......], P. Wang, Y. Watanabe, E. Won, Q. L. Xie, A. Yamaguchi, Y. Yamashita, Z. P. Zhang, V. Zhilich, V. Zhulanov, A. Zupanc
  [show abstract] [hide abstract]
  ABSTRACT: We study the following charmless baryonic three-body decays of B mesons: B+→pΛ̅ γ, B+→pΛ̅ π0, and B0→pΛ̅ π-. The partial branching fractions as a function of the baryon-antibaryon mass and the polar angle distributions of the proton in the baryon-antibaryon system are presented. This study includes the first observation of B+→pΛ̅ π0, which is measured to have a branching fraction of (3.00-0.53+0.61±0.33)×10-6. We also set upper limits on branching fractions of the two-body decays B0→pΣ̅ *-, B0→Δ0Λ̅ , B+→pΣ̅ *0, and B+→Δ+Λ̅ at the 90% confidence level. These results are obtained from a 414 fb-1 data sample collected near the Υ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider.
  Phys. Rev. D. 09/2007; 76(5).
• Article: Measurements of branching fractions for B --> K pi and B --> pi pi decays.

  S-W Lin, P Chang, K Abe, I Adachi, H Aihara, D Anipko, V Aulchenko, T Aushev, S Bahinipati, A M Bakich, [......], E Won, Q L Xie, B D Yabsley, A Yamaguchi, Y Yamashita, M Yamauchi, Y Yusa, C C Zhang, Z P Zhang, A Zupanc
  [show abstract] [hide abstract]
  ABSTRACT: We report measurements of branching fractions for B --> K pi and B --> pi pi decays based on a data sample of 449 x 10(6) BB[over] pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. We also measure the ratios of partial widths for B-->Kpi decays, namely R(c) identical with 2Gamma(B(+) --> K(+) pi(0))/Gamma(B(+) --> K(0) pi(+)) = 1.08+/-0.06+/-0.08 and R(n) identical with Gamma(B(0) --> K(+) pi(-))/2 Gamma(B(0) --> K(0) pi(0)) = 1.08+/-0.08+/-0.08, where the first and the second errors are statistical and systematic, respectively. These ratios are sensitive to enhanced electroweak penguin contributions from new physics; the new measurements are, however, consistent with standard model expectations.
  Physical Review Letters 09/2007; 99(12):121601. · 7.37 Impact Factor
• Article: Study of B̅ 0→D0π+π- decays

  A. Kuzmin, K. Abe, I. Adachi, H. Aihara, D. Anipko, K. Arinstein, V. Aulchenko, T. Aushev, S. Bahinipati, A. M. Bakich, [......], C.-H. Wu, Q. L. Xie, B. D. Yabsley, A. Yamaguchi, Y. Yamashita, M. Yamauchi, L. M. Zhang, Z. P. Zhang, V. Zhilich, A. Zupanc
  [show abstract] [hide abstract]
  ABSTRACT: We report the results of a study of neutral B meson decays to the D0π+π- final state, where the D0 is fully reconstructed. The results are obtained from an event sample containing 388×106 BB̅ -meson pairs collected in the Belle experiment at the KEKB e+e- collider. The total branching fraction of the three-body decay B(B̅ 0→D0π+π-)=(8.4±0.4(stat)±0.8(syst))×10-4 has been measured. The intermediate resonant structure of these three-body decays has been studied. From a Dalitz plot analysis we have obtained the product of the branching fractions for D2*+ and D0*+ production: B(B̅ 0→D2*+π-)×B(D2*+→D0π+)=(2.15±0.17(stat)±0.29(syst)±0.12(mod))×10-4, and B(B̅ 0→D0*+π-)×B(D0*+→D0π+)=(0.60±0.13(stat)±0.15(syst)±0.22(mod))×10-4. This is the first observation of the B̅ 0→D0*+π- decay. The B̅ 0→D0ρ0 and D0f2 branching fractions are measured to be: B(B̅ 0→D0ρ0)=(3.19±0.20(stat)±0.24(syst)±0.38(mod))×10-4, and B(B̅ 0→D0f2)=(1.20±0.18(stat)±0.21(syst)±0.32(mod))×10-4.
  Phys. Rev. D. 07/2007; 76(1).
• Article: Measurement of the tau lepton mass and an upper limit on the mass difference between tau+ and tau-.

  K Belous, M Shapkin, A Sokolov, K Abe, I Adachi, H Aihara, D Anipko, K Arinstein, V Aulchenko, T Aushev, [......], E Won, Q L Xie, B D Yabsley, A Yamaguchi, Y Yamashita, M Yamauchi, Z P Zhang, V Zhilich, V Zhulanov, A Zupanc
  [show abstract] [hide abstract]
  ABSTRACT: The mass of the tau lepton has been measured in the decay mode tau-->3pinutau using a pseudomass technique. The result obtained from 414 fb-1 of data collected with the Belle detector is Mtau=[1776.61+/-0.13(stat)+/-0.35(sys)] MeV/c2. The upper limit on the relative mass difference between positive and negative tau leptons is |Mtau+-Mtau-|/Mtau<2.8 x 10-4 at 90% confidence level.
  Physical Review Letters 07/2007; 99(1):011801. · 7.37 Impact Factor
• Article: Evidence for CP violation in B0-->D+D- decays.

  S Fratina, K Abe, I Adachi, H Aihara, D Anipko, K Arinstein, T Aushev, A M Bakich, E Barberio, A Bay, [......], Y Watanabe, E Won, B D Yabsley, A Yamaguchi, Y Yamashita, M Yamauchi, C C Zhang, Z P Zhang, V Zhilich, A Zupanc
  [show abstract] [hide abstract]
  ABSTRACT: We report measurements of the branching fraction and CP violation parameters in B(0)-->D+ D- decays. The results are based on a data sample that contains 535 x 10(6) BB pairs collected at the Upsilon(4S) resonance, with the Belle detector at the KEKB asymmetric-energy e+e- collider. We obtain [1.97+/-0.20(stat) +/- 0.20(syst)] x 10(-4) for the branching fraction of B0-->D+D-. The measured values of the CP violation parameters are S=-1.13+/-0.37+/-0.09, A=0.91+/-0.23+/-0.06, where the first error is statistical and the second is systematic. We find evidence of CP violation in B0-->D+D- at the 4.1sigma confidence level. While the value of S is consistent with expectations from other measurements, the value of the parameter A favors large direct CP violation at the 3.2sigma confidence level, in contradiction to standard model expectations.
  Physical Review Letters 06/2007; 98(22):221802. · 7.37 Impact Factor
• Source

  Available from: arxiv.org

  Article: Measurement of CP asymmetry in a time-dependent Dalitz analysis of B0-->(rhopi)0 and a constraint on the quark mixing matrix angle phi2.

  A Kusaka, C C Wang, H Ishino, K Abe, I Adachi, H Aihara, D Anipko, V Aulchenko, T Aushev, A M Bakich, [......], R Wedd, E Won, Q L Xie, B D Yabsley, A Yamaguchi, Y Yamashita, L M Zhang, Z P Zhang, V Zhilich, A Zupanc
  [show abstract] [hide abstract]
  ABSTRACT: We present a measurement of CP asymmetry using a time-dependent Dalitz plot analysis of B0-->pi+pi-pi0 decays based on a 414 fb(-1) data sample containing 449 x 10(6) BB pairs. The data was collected on the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric energy e+ e- collider. Combining our analysis with information on charged B decay modes, we perform a full Dalitz and isospin analysis and obtain a constraint on the CKM angle phi2, 68 degrees < phi2 < 95 degrees as the 68.3% confidence interval for the phi2 solution consistent with the standard model (SM). A large SM-disfavored region also remains.
  Physical Review Letters 06/2007; 98(22):221602. · 7.37 Impact Factor
• Article: Experimental constraints on the spin and parity of the Lambdac(2880)+.

  R Mizuk, K Abe, I Adachi, H Aihara, D Anipko, V Aulchenko, T Aushev, A M Bakich, V Balagura, E Barberio, [......], Q L Xie, B D Yabsley, A Yamaguchi, Y Yamashita, M Yamauchi, C Z Yuan, L M Zhang, Z P Zhang, V Zhilich, A Zupanc
  [show abstract] [hide abstract]
  ABSTRACT: We report the results of several studies of the Lambda(c)(+)pi(+)pi(-)X final state in continuum e(+)e(-) annihilation data collected by the Belle detector. An analysis of angular distributions in Lambda(c)(2880)(+)-->Sigma(c)(2455)(0,++)pi(+,-) decays strongly favors a Lambda(c)(2880)(+) spin assignment of 5/2 over 3/2 or 1/2. We find evidence for Lambda(c)(2880)(+)-->Sigma(c)(2520)(0,++)pi(+,-) decay and measure the ratio of Lambda(c)(2880)(+) partial widths Gamma(Sigma(c)(2520)pi)/Gamma(Sigma(c)(2455)pi)=0.225+/-0.062+/-0.025. This value favors the Lambda(c)(2880)(+) spin-parity assignment of 5/2(+) over 5/2(-). We also report the first observation of Lambda(c)(2940)(+)-->Sigma(c)(2455)(0,++)pi(+,-) decay and measure Lambda(c)(2880)(+) and Lambda(c)(2940)(+) mass and width parameters. These studies are based on a 553 fb(-1) data sample collected at or near the Upsilon(4S) resonance at the KEKB collider.
  Physical Review Letters 06/2007; 98(26):262001. · 7.37 Impact Factor
• Article: Search for B0→pp¯, ΛΛ¯ and B+→pΛ¯ at Belle

  Y.-T. Tsai, P. Chang, K. Abe, I. Adachi, H. Aihara, D. Anipko, A. M. Bakich, U. Bitenc, I. Bizjak, S. Blyth, [......], C. H. Wang, M.-Z. Wang, Y. Watanabe, E. Won, A. Yamaguchi, Y. Yamashita, M. Yamauchi, V. Zhilich, V. Zhulanov, A. Zupanc
  [show abstract] [hide abstract]
  ABSTRACT: We report on a new search for two-body baryonic decays of the B meson. Improved sensitivity compared to previous Belle results is obtained from 414fb-1 of data that corresponds to 449×106 BB¯ pairs, which were taken on the Υ(4S) resonance and collected with the Belle detector at the KEKB e+e- collider. No significant signals are observed and we set the 90% confidence level upper limits: B(B0→pp¯)<1.1×10-7, B(B0→ΛΛ¯)<3.2×10-7, and B(B+→pΛ¯)<3.2×10-7.
  Physical review D: Particles and fields 05/2007; 75(11):111101.
• Article: Search for B decays into η′p, η′K*, η′ϕ, η′ω and η′η(′)

  J. Schümann, C. H. Wang, K. Abe, H. Aihara, D. Anipko, K. Arinstein, V. Aulchenko, T. Aushev, A. M. Bakich, E. Barberio, [......], S. Villa, M.-Z. Wang, M. Watanabe, Y. Watanabe, E. Won, A. Yamaguchi, Y. Yamashita, M. Yamauchi, V. Zhilich, A. Zupanc
  [show abstract] [hide abstract]
  ABSTRACT: We report on a search for the exclusive two-body charmless hadronic B meson decays B→η′ρ, B→η′K*, B0→η′ϕ, B0→η′ω, and B0→η′η(′). The results are obtained from a data sample containing 535×106 BB̅ pairs that were collected at the Υ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. We find no significant signals and report upper limits in the range (0.5–6.5)×10-6 for all of the above decays.
  Phys. Rev. D. 05/2007; 75(9).
• Article: Observation of direct CP violation in B0 --> pi+pi- decays and model-independent constraints on the quark-mixing angle phi2.

  H Ishino, K Abe, I Adachi, H Aihara, D Anipko, K Arinstein, T Aushev, A M Bakich, E Barberio, M Barbero, [......], C-H Wu, Q L Xie, B D Yabsley, A Yamaguchi, Y Yamashita, M Yamauchi, L M Zhang, Z P Zhang, V Zhilich, A Zupanc
  [show abstract] [hide abstract]
  ABSTRACT: We report a new measurement of the time-dependent CP-violating parameters in B(0)-->pi(+)pi(-) decays with 535 x 10(6) BB pairs collected with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider operating at the Upsilon(4S) resonance. We find 1464+/-65 B(0)-->pi(+)pi(-) events and measure the CP-violating parameters S(pipi)=-0.61+/-0.10(stat)+/-0.04(syst) and A(pipi)=+0.55+/-0.08(stat)+/-0.05(syst). We observe large direct CP violation with a significance greater than 5 standard deviations for any S(pipi) value. Using isospin relations, we measure the Cabibbo-Kobayashi-Maskawa quark-mixing matrix angle phi(2)=(97+/-11) degrees for the solution consistent with the standard model and exclude the range 11 degrees <phi(2)<79 degrees at the 95% confidence level.
  Physical Review Letters 05/2007; 98(21):211801. · 7.37 Impact Factor
• Source

  Available from: arxiv.org

  Article: Observation of B decays to two kaons.

  S-W Lin, P Chang, K Abe, I Adachi, H Aihara, D Anipko, K Arinstein, V Aulchenko, T Aushev, T Aziz, [......], Q L Xie, B D Yabsley, A Yamaguchi, Y Yamashita, M Yamauchi, C C Zhang, L M Zhang, Z P Zhang, V Zhilich, A Zupanc
  [show abstract] [hide abstract]
  ABSTRACT: Using 449x10(6) BB[over ] pairs collected with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider, we observe clear signals for B(+)-->K[over ](0)K(+) and B(0)-->K[over ](0)K(0) decays with 5.3sigma and 6.0sigma significance, respectively. We measure the branching fractions B(B(+)-->K[over ](0)K(+))=(1.22(-0.28-0.16)(+0.32+0.13))x10(-6) and B(B(0)-->K[over ](0)K(0))=(0.87(-0.20)(+0.25)+/-0.09)x10(-6), and partial-rate asymmetries A(CP)(B(+)-->K[over ](0)K(+))=0.13(-0.24)(+0.23)+/-0.02 and A(CP)(B(0)-->K[over ](0)K(0))=-0.58(-0.66)(+0.73)+/-0.04. From a simultaneous fit, we also obtain B(B(+)-->K(0)pi(+))=(22.8(-0.7)(+0.8)+/-1.3)x10(-6) and A(CP)(B(+)-->K(0)pi(+))=0.03+/-0.03+/-0.01. The first and second error in the branching fractions and the partial-rate asymmetries are statistical and systematic, respectively. No signal is observed for B(0)-->K(+)K(-) decays, and for this branching fraction, we set an upper limit of 4.1x10(-7) at the 90% confidence level.
  Physical Review Letters 05/2007; 98(18):181804. · 7.37 Impact Factor
• Article: Measurement of the near-threshold e+e- --> D(*)+/-D(*)-/+ cross section using initial-state radiation.

  G Pakhlova, K Abe, I Adachi, H Aihara, D Anipko, V Aulchenko, T Aushev, A M Bakich, V Balagura, E Barberio, [......], Y Watanabe, E Won, Q L Xie, B D Yabsley, A Yamaguchi, Y Yamashita, C C Zhang, Z P Zhang, V Zhilich, A Zupanc
  [show abstract] [hide abstract]
  ABSTRACT: We report a measurement of the exclusive e+e- -->D(*)+/-D*-/+ cross section as a function of center-of-mass energy near the D(*)+/-D*-/+ threshold with initial-state radiation. A partial reconstruction technique is used to increase the efficiency and to suppress background. The analysis is based on a data sample collected with the Belle detector with an integrated luminosity of 547.8 fb(-1).
  Physical Review Letters 03/2007; 98(9):092001. · 7.37 Impact Factor
• Article: Observation of the decay B(0)-->J/psieta.

  M-C Chang, K Abe, I Adachi, H Aihara, D Anipko, K Arinstein, T Aushev, A M Bakich, E Barberio, A Bay, [......], E Won, Q L Xie, A Yamaguchi, Y Yamashita, M Yamauchi, Y Yusa, C C Zhang, L M Zhang, Z P Zhang, A Zupanc
  [show abstract] [hide abstract]
  ABSTRACT: We report the first observation of B(0)-->J/psieta decay. These results are obtained from a data sample that contains 449 x10(6) BB[over] pairs accumulated at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. We observe a signal with a significance of 8.1 sigma and obtain a branching fraction of (9.5+/-1.7(stat)+/-0.8(syst)) x 10(-6).
  Physical Review Letters 03/2007; 98(13):131803. · 7.37 Impact Factor
• Article: Search for invisible decay of the Upsilon(1S).

  O Tajima, H Hayashii, M Hazumi, K Inami, Y Iwasaki, S Uehara, K Abe, I Adachi, H Aihara, D Anipko, [......], J Wicht, E Won, Q L Xie, B D Yabsley, A Yamaguchi, Y Yamashita, M Yamauchi, Z P Zhang, V Zhilich, A Zupanc
  [show abstract] [hide abstract]
  ABSTRACT: We report results of a search for the invisible decay of the Upsilon(1S) via the Upsilon(3S)-->pi+ pi- Upsilon(1S) transition using a data sample of 2.9 fb-1 at the Upsilon(3S) resonance. The data were collected with the Belle detector at the KEKB asymmetric-energy e+ e- collider. No signal is found, and an upper limit for the branching fraction at the 90% confidence level is determined to be B(Upsilon(1S)-->invisible)<2.5 x 10(-3).
  Physical Review Letters 03/2007; 98(13):132001. · 7.37 Impact Factor
• Article: Moments of the electron energy spectrum and partial branching fraction of B→Xceν decays at the Belle detector

  P. Urquijo, E. Barberio, K. Abe, I. Adachi, H. Aihara, D. Anipko, V. Aulchenko, T. Aushev, M. Barbero, K. Belous, [......], Q. L. Xie, B. D. Yabsley, A. Yamaguchi, Y. Yamashita, M. Yamauchi, Y. Yusa, L. M. Zhang, Z. P. Zhang, V. Zhilich, A. Zupanc
  [show abstract] [hide abstract]
  ABSTRACT: We report a measurement of the inclusive electron energy spectrum for charmed semileptonic decays of B mesons in a 140 fb-1 data sample collected at the Υ(4S) resonance with the Belle detector at the KEKB asymmetric energy e+e- collider. We determine the first four moments of the electron energy spectrum for threshold values of the electron energy between 0.4 and 2.0 GeV. In addition, we provide values of the partial branching fraction (zeroth moment) for the same electron threshold energies, and independent measurements of the B+ and B0 partial branching fractions at 0.4 GeV and 0.6 GeV electron threshold energies. We measure the independent B+ and B0 partial branching fractions with electron threshold energies of 0.4 GeV to be ΔB(B+→Xceν)=(10.79±0.25(stat.)±0.27(sys.))% and ΔB(B0→Xceν)=(10.08±0.30(stat.)±0.22(sys.))%. Full correlations between all measurements are evaluated.
  Phys. Rev. D. 02/2007; 75(3).
• Article: Measurement of inclusive Ds, D0, and J/psi rates and determination of the Bs(*)Bs(*) production fraction in bb Events at the Upsilon(5S) resonance.

  A Drutskoy, K Abe, I Adachi, H Aihara, D Anipko, K Arinstein, V Aulchenko, T Aushev, S Banerjee, E Barberio, [......], Q L Xie, B D Yabsley, A Yamaguchi, Y Yamashita, M Yamauchi, Y Yusa, L M Zhang, Z P Zhang, V Zhilich, A Zupanc
  [show abstract] [hide abstract]
  ABSTRACT: The inclusive production of D(s), D(0), and J/psi mesons is studied using a 1.86 fb(-1) data sample collected on the Upsilon(5S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. The number of bb events in this Upsilon(5S) data sample is determined. We measure the branching fractions B(Upsilon(5S)-->D(s)X)/2=(23.6+/-1.2+/-3.6)%, B(Upsilon(5S)-->D(0)X)/2=(53.8+/-2.0+/-3.4)%, and B(Upsilon(5S)-->J/psiX)/2=(1.030+/-0.080+/-0.067)%. From the D(s) and D(0) inclusive branching fractions the ratio f(s)=(18.0+/-1.3+/-3.2)% of B(s)(*)B(s)(*) to the total bb quark pair production at the Upsilon(5S) energy is obtained in a model-dependent way.
  Physical Review Letters 02/2007; 98(5):052001. · 7.37 Impact Factor
• Article: Search for B+→J/ψη′K+ and B0→J/ψη′KS0 decays

  Q. L. Xie, K. Abe, I. Adachi, H. Aihara, D. Anipko, K. Arinstein, V. Aulchenko, T. Aushev, T. Aziz, S. Bahinipati, [......], R. Wedd, E. Won, A. Yamaguchi, Y. Yamashita, M. Yamauchi, C. C. Zhang, L. M. Zhang, Z. P. Zhang, V. Zhilich, A. Zupanc
  [show abstract] [hide abstract]
  ABSTRACT: We report the results of searches for B+→J/ψη′K+ and B0→J/ψη′KS0 decays, using a sample of 388×106 BB̅ pairs collected with the Belle detector at the Υ(4S) resonance. No statistically significant signal is found for either of the two decay modes and upper limits for the branching fractions are determined to be B(B+→J/ψη′K+)<8.8×10-5 and B(B0→J/ψη′KS0)<2.5×10-5 at 90% confidence level.
  Phys. Rev. D. 01/2007; 75(1).
• Article: Observation of time-dependent CP violation in B0 --> eta'K0 decays and improved measurements of CP asymmetries in B0 --> phiK0, KS0KS0KS0 and B0 --> J/psiK0 decays.

  K-F Chen, K Hara, M Hazumi, T Higuchi, K Miyabayashi, Y Nakahama, K Sumisawa, O Tajima, Y Ushiroda, Y Yusa, [......], E Won, Q L Xie, B D Yabsley, A Yamaguchi, Y Yamashita, M Yamauchi, C C Zhang, Z P Zhang, V Zhilich, A Zupanc
  [show abstract] [hide abstract]
  ABSTRACT: We present improved measurements of CP-violation parameters in B(0) --> phiK(0), eta(')K(0), KS(0)KS(0)KS(0) decays based on a sample of 535 x 10(6) BB pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB energy-asymmetric e(+)e(-) collider. We obtain sin2phi1(eff)=+0.64+/-0.10(stat)+/-0.04(syst) for B(0) --> eta(')K(0), +0.50+/-0.21(stat)+/-0.06(syst) for B(0) --> phiK(0), and +0.30+/-0.32(stat)+/-0.08(syst) for B(0) --> KS(0)KS(0)KS(0) decays. We have observed CP violation in the B(0) --> eta(')K(0) decay with a significance of 5.6 standard deviations. We also perform an improved measurement of CP asymmetries in B(0) --> J/psiK(0) decays and obtain sin2phi1=+0.642+/-0.031(stat)+/-0.017(syst).
  Physical Review Letters 01/2007; 98(3):031802. · 7.37 Impact Factor