Measurement of CP asymmetries and branching fractions in charmless two-body B-meson decays to pions and kaons
Name
Lees-2013-Measurement of CP asymmetries and branching fractions.pdf
Size
702.13 KB
Format
Adobe PDF
Checksum (MD5)
5e3ee061a25365fcc215159db9ad1edb
Author(s)
Dujmic, Denis
Sciolla, Gabriella
Cowan, Ray F
Date Issued
March 2013
Journal
Physical Review D
Publisher
American Physical Society
Citation
Lees, J. P., V. Poireau, V. Tisserand, J. Garra Tico, E. Grauges, A. Palano, G. Eigen, et al. "Measurement of CP Asymmetries and Branching Fractions in Charmless Two-body B-meson Decays to Pions and Kaons." Physical Review D 87, no. 5 (March 2013). © 2013 American Physical Society.
Version
Final published version
Abstract
We present improved measurements of CP-violation parameters in the decays B[superscript 0]-->π+π-, B[superscript 0]-->K+π-, and B[superscript 0]-->π[superscript 0]π[superscript 0], and of the branching fractions for B[superscript 0]-->π[superscript 0]π[superscript 0] and B[superscript 0]-->K[superscript 0]π[superscript 0]. The results are obtained with the full data set collected at the Υ(4S) resonance by the BABAR experiment at the PEP-II asymmetric-energy B factory at the SLAC National Accelerator Laboratory, corresponding to (467±5)×10[superscript 6] BB̅ pairs. We find the CP-violation parameter values and branching fractions: Sπ+π-=-0.68±0.10±0.03, Cπ+π-=-0.25±0.08±0.02, AK-π+=-0.107±0.016[subscript -0.004][superscript +0.006], Cπ0π0=-0.43±0.26±0.05, B(B0-->π0π0)=(1.83±0.21±0.13)×10-6, B(B[superscript 0]-->K[superscript 0]π[superscript 0])= (10.1±0.6±0.4)×10-6, where in each case, the first uncertainties are statistical and the second are systematic. We observe CP violation with a significance of 6.7 standard deviations for B[superscript 0]-->π+π- and 6.1 standard deviations for B0-->K+π-, including systematic uncertainties. Constraints on the unitarity triangle angle α are determined from the isospin relations among the B-->ππ rates and asymmetries. Considering only the solution preferred by the Standard Model, we find α to be in the range [71°,109°] at the 68% confidence level.
MIT Department
Massachusetts Institute of Technology. Laboratory for Nuclear Science
Terms of Use
Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.
Persistent DSpace Link
DOI of Published Version
http://dx.doi.org/10.1103/PhysRevD.87.052009
