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Title: Direct CP violation in B{sup 0}{yields}{rho}{sup 0}({omega}){rho}{sup 0}({omega}){yields}{pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -}

Abstract

We study the direct CP violation in B{sup 0}{yields}{rho}{sup 0}({omega}){rho}{sup 0}({omega}){yields}{pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} [with unpolarized {rho}{sup 0}({omega})] via the {rho}-{omega} mixing mechanism which causes a large strong phase difference and consequently a large CP violating asymmetry when the masses of the {pi}{sup +}{pi}{sup -} pairs are in the vicinity of the {omega} resonance. Since there are two {rho}({omega}) mesons in the intermediate state {rho}-{omega} mixing contributes twice to the first order of isospin violation, leading to an even larger CP violating asymmetry (it could be 30%-50% larger) than in the case where only one {rho}({omega}) meson is involved. The CP violating asymmetry depends on the Cabibbo-Kobayashi-Maskawa (CKM) matrix elements and the hadronic matrix elements. The factorization approach is applied in the calculation of the hadronic matrix elements with the nonfactorizable effects being included effectively in an effective parameter, N{sub c}. We give the constraint on the range of N{sub c} from the latest experimental data for the branching ratios for B{sup 0}{yields}{rho}{sup 0}{rho}{sup 0} and B{sup 0}{yields}{rho}{sup +}{rho}{sup -}. We find that the CP violating asymmetry could be very large (even more than 90% for some values of N{sub c}). It is shown that the sensitivity of themore » CP violating asymmetry to N{sub c} is large compared with its smaller sensitivity to the CKM matrix elements. We also discuss the possibility to remove the mod ({pi}) ambiguity in the determination of the CP violating phase angle {alpha} through the measurement of the CP violating asymmetry in the decay B{sup 0}{yields}{rho}{sup 0}({omega}){rho}{sup 0}({omega}){yields}{pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -}.« less

Authors:
;  [1]
  1. Institute of Low Energy Nuclear Physics, Beijing Normal University, Beijing 100875 (China)
Publication Date:
OSTI Identifier:
21020288
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 7; Other Information: DOI: 10.1103/PhysRevD.75.074028; (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; BRANCHING RATIO; CP INVARIANCE; FACTORIZATION; INTERMEDIATE STATE; ISOSPIN; KOBAYASHI-MASKAWA MATRIX; MATRIX ELEMENTS; OMEGA-782 MESONS; PARTICLE DECAY; PIONS MINUS; PIONS PLUS; RHO-770 MESONS; SENSITIVITY; STANDARD MODEL

Citation Formats

Guo, X.-H., and Zhang, Z.-H. Direct CP violation in B{sup 0}{yields}{rho}{sup 0}({omega}){rho}{sup 0}({omega}){yields}{pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -}. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.074028.
Guo, X.-H., & Zhang, Z.-H. Direct CP violation in B{sup 0}{yields}{rho}{sup 0}({omega}){rho}{sup 0}({omega}){yields}{pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -}. United States. doi:10.1103/PHYSREVD.75.074028.
Guo, X.-H., and Zhang, Z.-H. Sun . "Direct CP violation in B{sup 0}{yields}{rho}{sup 0}({omega}){rho}{sup 0}({omega}){yields}{pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -}". United States. doi:10.1103/PHYSREVD.75.074028.
@article{osti_21020288,
title = {Direct CP violation in B{sup 0}{yields}{rho}{sup 0}({omega}){rho}{sup 0}({omega}){yields}{pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -}},
author = {Guo, X.-H. and Zhang, Z.-H.},
abstractNote = {We study the direct CP violation in B{sup 0}{yields}{rho}{sup 0}({omega}){rho}{sup 0}({omega}){yields}{pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} [with unpolarized {rho}{sup 0}({omega})] via the {rho}-{omega} mixing mechanism which causes a large strong phase difference and consequently a large CP violating asymmetry when the masses of the {pi}{sup +}{pi}{sup -} pairs are in the vicinity of the {omega} resonance. Since there are two {rho}({omega}) mesons in the intermediate state {rho}-{omega} mixing contributes twice to the first order of isospin violation, leading to an even larger CP violating asymmetry (it could be 30%-50% larger) than in the case where only one {rho}({omega}) meson is involved. The CP violating asymmetry depends on the Cabibbo-Kobayashi-Maskawa (CKM) matrix elements and the hadronic matrix elements. The factorization approach is applied in the calculation of the hadronic matrix elements with the nonfactorizable effects being included effectively in an effective parameter, N{sub c}. We give the constraint on the range of N{sub c} from the latest experimental data for the branching ratios for B{sup 0}{yields}{rho}{sup 0}{rho}{sup 0} and B{sup 0}{yields}{rho}{sup +}{rho}{sup -}. We find that the CP violating asymmetry could be very large (even more than 90% for some values of N{sub c}). It is shown that the sensitivity of the CP violating asymmetry to N{sub c} is large compared with its smaller sensitivity to the CKM matrix elements. We also discuss the possibility to remove the mod ({pi}) ambiguity in the determination of the CP violating phase angle {alpha} through the measurement of the CP violating asymmetry in the decay B{sup 0}{yields}{rho}{sup 0}({omega}){rho}{sup 0}({omega}){yields}{pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -}.},
doi = {10.1103/PHYSREVD.75.074028},
journal = {Physical Review. D, Particles Fields},
number = 7,
volume = 75,
place = {United States},
year = {Sun Apr 01 00:00:00 EDT 2007},
month = {Sun Apr 01 00:00:00 EDT 2007}
}
  • We study direct CP violation in B{sup {+-}}{yields}{rho}{sup {+-}}{rho}{sup 0}({omega}){yields}{rho}{sup {+-}}{pi}{sup +}{pi}{sup -} and focus specifically on the rate asymmetry in the {rho}{sup 0}-{omega} interference region. Here the strong phase is dominated by isospin violation, so that it can be essentially determined by e{sup +}e{sup -}{yields}{rho}{sup 0}({omega}){yields}{pi}{sup +}{pi}{sup -} data. We find the CP-violating asymmetry to be the order of 20% at the {omega} invariant mass. Moreover, it is robust with respect to the estimatable strong-phase uncertainties, permitting the extraction of sin {alpha} from this channel.
  • We report results on a Dalitz analysis of three-body charmless B{sup {+-}}{yields}K{sup {+-}}{pi}{sup {+-}}{pi}{sup {+-}} decay including searches for direct CP violation. We report the first observation of the decay B{sup {+-}}{yields}f{sub 2}(1270)K{sup {+-}} with a statistical significance above 6{sigma}. We also observe first evidence for large direct CP violation in the B{sup {+-}}{yields}{rho}(770){sup 0}K{sup {+-}} channel. The results are obtained with a data sample that contains 386x10{sup 6} BB pairs collected at the {upsilon}(4S) resonance with the Belle detector at the KEKB asymmetric-energy e{sup +}e{sup -} collider.
  • We present evidence for the b{yields}d penguin-dominated decays B{sup +}{yields}K{sup 0}K{sup +} and B{sup 0}{yields}K{sup 0}K{sup 0} in 227x10{sup 6} {upsilon}(4S){yields}BB decays collected with the BABAR detector. We measure the branching fractions B(B{sup +}{yields}K{sup 0}K{sup +})=(1.5{+-}0.5{+-}0.1)x10{sup -6}(<2.4x10{sup -6}) and B(B{sup 0}{yields}K{sup 0}K{sup 0})=(1.19{sub -0.35}{sup +0.40}{+-}0.13)x10{sup -6}, where the uncertainties are statistical and systematic, respectively. We also present improved measurements of the charge-averaged branching fraction B(B{sup +}{yields}K{sup 0}{pi}{sup +})=(26.0{+-}1.3{+-}1.0)x10{sup -6} and CP-violating charge asymmetry A{sub CP}(K{sup 0}{pi}{sup +})=-0.09{+-}0.05{+-}0.01, where the uncertainties are statistical and systematic, respectively.
  • We present measurements of time-dependent CP asymmetries in B{sup 0}{yields}{omega}K{sub S}{sup 0}, f{sub 0}(980)K{sub S}{sup 0}, K{sub S}{sup 0}{pi}{sup 0} and K{sup +}K{sup -}K{sub S}{sup 0} decays based on a sample of 535x10{sup 6} BB pairs collected at the {upsilon}(4S) resonance with the Belle detector at the KEKB energy-asymmetric e{sup +}e{sup -} collider. One neutral B meson is fully reconstructed in one of the specified decay channels, and the flavor of the accompanying B meson is identified from its decay products. CP-violation parameters for each of the decay modes are obtained from the asymmetries in the distributions of the proper-timemore » intervals between the two B decays.« less
  • We present measurements of the branching fractions, longitudinal polarization, and direct CP-violation asymmetries for the decays B{sup +}{yields}{rho}{sup 0}K*{sup +} and B{sup +}{yields}f{sub 0}(980)K*{sup +} with a sample of (467{+-}5)x10{sup 6}BB pairs collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at the SLAC National Accelerator Laboratory. We observe B{sup +}{yields}{rho}{sup 0}K{sup *+} with a significance of 5.3{sigma} and measure the branching fraction B(B{sup +}{yields}{rho}{sup 0}K{sup *+})=(4.6{+-}1.0{+-}0.4)x10{sup -6}, the longitudinal polarization f{sub L}=0.78{+-}0.12{+-}0.03, and the CP-violation asymmetry A{sub CP}=0.31{+-}0.13{+-}0.03. We observe B{sup +}{yields}f{sub 0}(980)K*{sup +} and measure the branching fraction B(B{sup +}{yields}f{sub 0}(980)K*{sup +})xB(f{sub 0}(980){yields}{pi}{sup +}{pi}{supmore » -})=(4.2{+-}0.6{+-}0.3)x10{sup -6} and the CP-violation asymmetry A{sub CP}=-0.15{+-}0.12{+-}0.03. The first uncertainty quoted is statistical and the second is systematic.« less