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Title: Measurement of the CP Asymmetry and Branching Fraction of B{sup 0}{yields}{rho}{sup 0}K{sup 0}

Abstract

We present a measurement of the branching fraction and time-dependent CP asymmetry of B{sup 0}{yields}{rho}{sup 0}K{sup 0}. The results are obtained from a data sample of 227x10{sup 6} {upsilon}(4S){yields}BB decays collected with the BABAR detector at the PEP-II asymmetric-energy B factory at Stanford Linear Accelerator Center. From a time-dependent maximum likelihood fit yielding 111{+-}19 signal events, we find B(B{sup 0}{yields}{rho}{sup 0}K{sup 0})=(4.9{+-}0.8{+-}0.9)x10{sup -6}, where the first error is statistical and the second systematic. We report the measurement of the CP parameters S{sub {rho}{sup 0}}{sub K{sub S}{sup 0}}=0.20{+-}0.52{+-}0.24 and C{sub {rho}{sup 0}}{sub K{sub S}{sup 0}}=0.64{+-}0.41{+-}0.20.

Authors:
; ; ; ; ; ; ; ; ;  [1];  [2];  [3]; ; ; ; ;  [4]; ; ;  [5]
  1. Laboratoire de Physique des Particules, F-74941 Annecy-le-Vieux (France)
  2. Universitat de Barcelona, Facultat de Fisica Departament ECM, E-08028 Barcelona (Spain)
  3. Universita di Bari, Dipartimento di Fisica and INFN, I-70126 Bari (Italy)
  4. Institute of High Energy Physics, Beijing 100039 (China)
  5. University of Bergen, Institute of Physics, N-5007 Bergen (Norway) (and others)
Publication Date:
OSTI Identifier:
20955416
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevLett.98.051803; (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; ERRORS; KAONS NEUTRAL SHORT-LIVED; MAXIMUM-LIKELIHOOD FIT; PARTICLE DECAY; PARTICLE PRODUCTION; RHO-770 MESONS; SIGNALS; STANFORD LINEAR ACCELERATOR CENTER; TIME DEPENDENCE

Citation Formats

Aubert, B., Barate, R., Bona, M., Boutigny, D., Couderc, F., Karyotakis, Y., Lees, J. P., Poireau, V., Tisserand, V., Zghiche, A., Grauges, E., Palano, A., Chen, J. C., Qi, N. D., Rong, G., Wang, P., Zhu, Y. S., Eigen, G., Ofte, I., and Stugu, B. Measurement of the CP Asymmetry and Branching Fraction of B{sup 0}{yields}{rho}{sup 0}K{sup 0}. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.051803.
Aubert, B., Barate, R., Bona, M., Boutigny, D., Couderc, F., Karyotakis, Y., Lees, J. P., Poireau, V., Tisserand, V., Zghiche, A., Grauges, E., Palano, A., Chen, J. C., Qi, N. D., Rong, G., Wang, P., Zhu, Y. S., Eigen, G., Ofte, I., & Stugu, B. Measurement of the CP Asymmetry and Branching Fraction of B{sup 0}{yields}{rho}{sup 0}K{sup 0}. United States. doi:10.1103/PHYSREVLETT.98.051803.
Aubert, B., Barate, R., Bona, M., Boutigny, D., Couderc, F., Karyotakis, Y., Lees, J. P., Poireau, V., Tisserand, V., Zghiche, A., Grauges, E., Palano, A., Chen, J. C., Qi, N. D., Rong, G., Wang, P., Zhu, Y. S., Eigen, G., Ofte, I., and Stugu, B. Fri . "Measurement of the CP Asymmetry and Branching Fraction of B{sup 0}{yields}{rho}{sup 0}K{sup 0}". United States. doi:10.1103/PHYSREVLETT.98.051803.
@article{osti_20955416,
title = {Measurement of the CP Asymmetry and Branching Fraction of B{sup 0}{yields}{rho}{sup 0}K{sup 0}},
author = {Aubert, B. and Barate, R. and Bona, M. and Boutigny, D. and Couderc, F. and Karyotakis, Y. and Lees, J. P. and Poireau, V. and Tisserand, V. and Zghiche, A. and Grauges, E. and Palano, A. and Chen, J. C. and Qi, N. D. and Rong, G. and Wang, P. and Zhu, Y. S. and Eigen, G. and Ofte, I. and Stugu, B.},
abstractNote = {We present a measurement of the branching fraction and time-dependent CP asymmetry of B{sup 0}{yields}{rho}{sup 0}K{sup 0}. The results are obtained from a data sample of 227x10{sup 6} {upsilon}(4S){yields}BB decays collected with the BABAR detector at the PEP-II asymmetric-energy B factory at Stanford Linear Accelerator Center. From a time-dependent maximum likelihood fit yielding 111{+-}19 signal events, we find B(B{sup 0}{yields}{rho}{sup 0}K{sup 0})=(4.9{+-}0.8{+-}0.9)x10{sup -6}, where the first error is statistical and the second systematic. We report the measurement of the CP parameters S{sub {rho}{sup 0}}{sub K{sub S}{sup 0}}=0.20{+-}0.52{+-}0.24 and C{sub {rho}{sup 0}}{sub K{sub S}{sup 0}}=0.64{+-}0.41{+-}0.20.},
doi = {10.1103/PHYSREVLETT.98.051803},
journal = {Physical Review Letters},
number = 5,
volume = 98,
place = {United States},
year = {Fri Feb 02 00:00:00 EST 2007},
month = {Fri Feb 02 00:00:00 EST 2007}
}
  • 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.
  • We report a measurement of the branching fraction of the decay B{sup 0}{yields}{rho}{sup 0}{pi}{sup 0}, using 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 detect 51{sub -13}{sup +14} signal events with a significance of 4.2 standard deviations, including systematic uncertainties, and measure the branching fraction to be B(B{sup 0}{yields}{rho}{sup 0}{pi}{sup 0})=(3.12{sub -0.82}{sup +0.88}(stat){+-}0.33(syst){sub -0.6=} 8{sup +0.50}(model))x10{sup -6}. We also perform the first measurement of direct CP violating asymmetry in this mode.
  • 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 improved measurements of the branching fraction and CP asymmetry for the process B{sup {+-}}{yields}{rho}{sup {+-}}{pi}{sup 0}. The data sample corresponding to 211 fb{sup -1} comprises 232x10{sup 6} {upsilon}(4S){yields}BB decays collected with the BABAR detector at the PEP-II asymmetric B Factory at SLAC. The yield and CP asymmetry are measured using an extended maximum likelihood fitting method. The branching fraction and CP asymmetry are found to be B(B{sup {+-}}{yields}{rho}{sup {+-}}{pi}{sup 0})=[10.2{+-}1.4(stat){+-}0.9(syst)]x10{sup -6} and A{sub CP}(B{sup {+-}}{yields}{rho}{sup {+-}}{pi}{sup 0})=-0.01{+-}0.13(stat){+-}0.02(syst)
  • We measure the branching fraction and the CP-violating asymmetry of B{sup 0}{yields}K{sub S}{sup 0}{pi}{sup 0} decays with 227 million {upsilon}(4S){yields}BB events collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at SLAC. We obtain a branching fraction B(B{sup 0}{yields}K{sup 0}{pi}{sup 0})=(11.4{+-}0.9{+-}0.6)x10{sup -6} and CP-violating asymmetry parameters C{sub K{sub S}{sup 0}}{pi}{sup 0}=0.06{+-}0.18{+-}0.03 and S{sub K{sup 0}}{pi}{sup 0}=0.35{sub -0.33}{sup +0.30}{+-}0.04, where the first error is statistical and the second systematic.