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Title: Measurement of CP Asymmetry in a Time-Dependent Dalitz Analysis of B{sup 0}{yields}({rho}{pi}){sup 0} and a Constraint on the Quark Mixing Matrix Angle {phi}{sub 2}

Abstract

We present a measurement of CP asymmetry using a time-dependent Dalitz plot analysis of B{sup 0}{yields}{pi}{sup +}{pi}{sup -}{pi}{sup 0} decays based on a 414 fb{sup -1} data sample containing 449x10{sup 6}BB pairs. The data was collected on the {upsilon}(4S) resonance with the Belle detector at the KEKB asymmetric energy e{sup +}e{sup -} 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 {phi}{sub 2}, 68 deg. <{phi}{sub 2}<95 deg. as the 68.3% confidence interval for the {phi}{sub 2} solution consistent with the standard model (SM). A large SM-disfavored region also remains.

Authors:
; ; ; ; ;  [1]; ; ; ; ; ; ; ;  [2]; ; ;  [3]; ; ;  [4]
  1. Department of Physics, University of Tokyo, Tokyo (Japan)
  2. Department of Physics, National Taiwan University, Taipei (China)
  3. Tokyo Institute of Technology, Tokyo (Japan)
  4. High Energy Accelerator Research Organization (KEK), Tsukuba (Japan) (and others)
Publication Date:
OSTI Identifier:
20951440
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 22; Other Information: DOI: 10.1103/PhysRevLett.98.221602; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ASYMMETRY; B NEUTRAL MESONS; CP INVARIANCE; DALITZ PLOT; ISOSPIN; MATHEMATICAL SOLUTIONS; PARTICLE DECAY; PARTICLE PRODUCTION; PIONS MINUS; PIONS NEUTRAL; PIONS PLUS; QUARKS; RESONANCE; STANDARD MODEL; TIME DEPENDENCE

Citation Formats

Kusaka, A., Aihara, H., Hastings, N. C., Ishikawa, A., Iwasaki, M., Kakuno, H., Wang, C. C., Chang, P., Chao, Y., Chen, K.-F., Hou, W.-S., Hsiung, Y. B., Lin, S.-W., Wang, M.-Z., Ishino, H., Khan, H. R., Watanabe, Y., Abe, K., Adachi, I., and Dragic, J.. Measurement of CP Asymmetry in a Time-Dependent Dalitz Analysis of B{sup 0}{yields}({rho}{pi}){sup 0} and a Constraint on the Quark Mixing Matrix Angle {phi}{sub 2}. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.221602.
Kusaka, A., Aihara, H., Hastings, N. C., Ishikawa, A., Iwasaki, M., Kakuno, H., Wang, C. C., Chang, P., Chao, Y., Chen, K.-F., Hou, W.-S., Hsiung, Y. B., Lin, S.-W., Wang, M.-Z., Ishino, H., Khan, H. R., Watanabe, Y., Abe, K., Adachi, I., & Dragic, J.. Measurement of CP Asymmetry in a Time-Dependent Dalitz Analysis of B{sup 0}{yields}({rho}{pi}){sup 0} and a Constraint on the Quark Mixing Matrix Angle {phi}{sub 2}. United States. doi:10.1103/PHYSREVLETT.98.221602.
Kusaka, A., Aihara, H., Hastings, N. C., Ishikawa, A., Iwasaki, M., Kakuno, H., Wang, C. C., Chang, P., Chao, Y., Chen, K.-F., Hou, W.-S., Hsiung, Y. B., Lin, S.-W., Wang, M.-Z., Ishino, H., Khan, H. R., Watanabe, Y., Abe, K., Adachi, I., and Dragic, J.. Fri . "Measurement of CP Asymmetry in a Time-Dependent Dalitz Analysis of B{sup 0}{yields}({rho}{pi}){sup 0} and a Constraint on the Quark Mixing Matrix Angle {phi}{sub 2}". United States. doi:10.1103/PHYSREVLETT.98.221602.
@article{osti_20951440,
title = {Measurement of CP Asymmetry in a Time-Dependent Dalitz Analysis of B{sup 0}{yields}({rho}{pi}){sup 0} and a Constraint on the Quark Mixing Matrix Angle {phi}{sub 2}},
author = {Kusaka, A. and Aihara, H. and Hastings, N. C. and Ishikawa, A. and Iwasaki, M. and Kakuno, H. and Wang, C. C. and Chang, P. and Chao, Y. and Chen, K.-F. and Hou, W.-S. and Hsiung, Y. B. and Lin, S.-W. and Wang, M.-Z. and Ishino, H. and Khan, H. R. and Watanabe, Y. and Abe, K. and Adachi, I. and Dragic, J.},
abstractNote = {We present a measurement of CP asymmetry using a time-dependent Dalitz plot analysis of B{sup 0}{yields}{pi}{sup +}{pi}{sup -}{pi}{sup 0} decays based on a 414 fb{sup -1} data sample containing 449x10{sup 6}BB pairs. The data was collected on the {upsilon}(4S) resonance with the Belle detector at the KEKB asymmetric energy e{sup +}e{sup -} 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 {phi}{sub 2}, 68 deg. <{phi}{sub 2}<95 deg. as the 68.3% confidence interval for the {phi}{sub 2} solution consistent with the standard model (SM). A large SM-disfavored region also remains.},
doi = {10.1103/PHYSREVLETT.98.221602},
journal = {Physical Review Letters},
number = 22,
volume = 98,
place = {United States},
year = {Fri Jun 01 00:00:00 EDT 2007},
month = {Fri Jun 01 00:00:00 EDT 2007}
}
  • We present the results of a time-dependent Dalitz plot analysis of B{sup 0}{yields}{pi}{sup +}{pi}{sup -}{pi}{sup 0} decays based on a 414 fb{sup -1} data sample that contains 449x10{sup 6}BB pairs. The data were collected on the {upsilon}(4S) resonance with the Belle detector at the KEKB asymmetric energy e{sup +}e{sup -} 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 quark mixing angle {phi}{sub 2}, 68 deg. <{phi}{sub 2}<95 deg. at the 68.3% confidence level for the {phi}{sub 2} solution consistent with the standard model.more » A large standard-model-disfavored region also remains. The branching fractions for the decay processes B{sup 0}{yields}{rho}{sup {+-}}(770){pi}{sup {+-}} and B{sup 0}{yields}{rho}{sup 0}(770){pi}{sup 0} are measured to be (22.6{+-}1.1[stat]{+-}4.4[syst])x10{sup -6} and (3.0{+-}0.5[stat]{+-}0.7[syst])x10{sup -6}, respectively. These are the first branching fraction measurements of the process B{sup 0}{yields}{rho}(770){pi} with the lowest resonance {rho}(770) explicitly separated from the radial excitations.« less
  • We present a measurement of the angle {phi}{sub 1} of the Cabibbo-Kobayashi-Maskawa unitarity triangle using a time-dependent Dalitz analysis of D{yields}K{sub S}{sup 0}{pi}{sup +}{pi}{sup -} decays produced in neutral B meson decay to a neutral D meson and a light meson (B{sup 0}{yields}D{sup (*)}h{sup 0}). The method allows a direct extraction of 2{phi}{sub 1} and, therefore, helps to resolve the ambiguity between 2{phi}{sub 1} and {pi}-2{phi}{sub 1} in the measurement of sin2{phi}{sub 1}. We obtain sin2{phi}{sub 1}=0.78{+-}0.44{+-}0.22 and cos2{phi}{sub 1}=1.87{sub -0.53-0.32}{sup +0.40+0.22}. The sign of cos2{phi}{sub 1} is determined to be positive at 98.3% C.L.
  • We report a new measurement of the time-dependent CP-violating parameters in B{sup 0}{yields}{pi}{sup +}{pi}{sup -} decays with 535x10{sup 6} BB pairs collected with the Belle detector at the KEKB asymmetric-energy e{sup +}e{sup -} collider operating at the {upsilon}(4S) resonance. We find 1464{+-}65 B{sup 0}{yields}{pi}{sup +}{pi}{sup -} events and measure the CP-violating parameters S{sub {pi}}{sub {pi}}=-0.61{+-}0.10(stat){+-}0.04(syst) and A{sub {pi}}{sub {pi}}=+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{sub {pi}}{sub {pi}} value. Using isospin relations, we measure the Cabibbo-Kobayashi-Maskawa quark-mixing matrix angle {phi}{sub 2}=(97{+-}11) deg. for the solution consistent with the standard modelmore » and exclude the range 11 deg. <{phi}{sub 2}<79 deg. at the 95% confidence level.« less
  • We present a time-dependent Dalitz plot measurement of CP violation parameters in B{sup 0}{yields}K{sub S}{sup 0}{pi}{sup +}{pi}{sup -} decays. These results are obtained from a large data sample that contains 657x10{sup 6} BB pairs collected at the {upsilon}(4S) resonance with the Belle detector at the KEKB asymmetric-energy e{sup +}e{sup -} collider. For the CP violation parameters, we obtain two consistent solutions that describe the data well. The first of these solutions may be preferred by external information from other measurements. There is no evidence for direct CP violation in B{sup 0}{yields}{rho}{sup 0}(770)K{sub S}{sup 0}, B{sup 0}{yields}f{sub 0}(980)K{sub S}{sup 0} andmore » B{sup 0}{yields}K*{sup +}(892){pi}{sup -}, while measurements of mixing-induced CP violation in B{sup 0}{yields}{rho}{sup 0}(770)K{sub S}{sup 0} and B{sup 0}{yields}f{sub 0}(980)K{sub S}{sup 0} decays are consistent with that of b{yields}ccs decays. We also measured the phase difference between B{sup 0}{yields}K*{sup +}(892){pi}{sup -} and B{sup 0}{yields}K{sup -}(892){pi}{sup +}, which may be used to extract {phi}{sub 3}.« less
  • We have measured the branching fraction B, longitudinal polarization fraction f{sub L}, and CP asymmetry coefficients A and S for B{sup 0}{yields}{rho}{sup +}{rho}{sup -} decays with the Belle detector at the KEKB e{sup +}e{sup -} collider using 253 fb{sup -1} of data. We obtain B=[22.8{+-}3.8(stat){sub -2.6}{sup +2.3}(syst)]x10{sup -6}, f{sub L}=0.941{sub -0.040}{sup +0.034}(stat){+-}0.030(syst), A=0.00{+-}0.30(stat){+-}0.09(syst), and S=0.08{+-}0.41(stat){+-}0.09(syst). These values are used to constrain the Cabibbo-Kobayashi-Maskawa phase {phi}{sub 2}; the solution consistent with the standard model is {phi}{sub 2}=(88{+-}17) deg. or 59 deg. <{phi}{sub 2}<115 deg. at 90% C.L.