Measurement of the Branching Fraction, Polarization, and $C P$ Asymmetry for $B^{0} \to ρ^{+} ρ^{-}$ Decays, and Determination of the Cabibbo-Kobayashi-Maskawa Phase $ϕ_{2}$

Publisher Website

2 May 2006

journal article
research article
Published by American Physical Society (APS) in Physical Review Letters

Vol. 96 (17) , 171801
https://doi.org/10.1103/physrevlett.96.171801

Abstract

We have measured the branching fraction

B

, longitudinal polarization fraction

f_{L}

, and

C P

asymmetry coefficients

A

and

S

for

B^{0} \to ρ^{+} ρ^{-}

decays with the Belle detector at the KEKB

e^{+} e^{-}

collider using

253 {fb}^{- 1}

of data. We obtain

B = [22.8 \pm 3.8 (stat)_{- 2.6}^{+ 2.3} (syst)] \times 10^{- 6}

,

f_{L} = {0.941}_{- 0.040}^{+ 0.034} (stat) \pm 0.030 (syst)

,

A = 0.00 \pm 0.30 (stat) \pm 0.09 (syst)

, and

S = 0.08 \pm 0.41 (stat) \pm 0.09 (syst)

. These values are used to constrain the Cabibbo-Kobayashi-Maskawa phase

ϕ_{2}

; the solution consistent with the standard model is

ϕ_{2} = (88 \pm 17) °

or

59 ° < ϕ_{2} < 115 °

at 90% C.L.

Keywords

All Related Versions

This publication has 16 references indexed in Scilit:

Time-dependent $C P$ -violating asymmetries in $b \to s \bar{q} q$ transitions
Physical Review D, 2005
Limit on the $B^{0} \to ρ^{0} ρ^{0}$ Branching Fraction and Implications for the Cabibbo-Kobayashi-Maskawa Angle $α$
Physical Review Letters, 2005
Neutral $B$ flavor tagging for the measurement of mixing-induced $CP$ violation at Belle
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2004
Evidence for $B^{0} \to π^{0} π^{0}$
Physical Review Letters, 2003
Impact of tag-side interference on time-dependentCPasymmetry measurements using coherent $B^{0} B^{0}$ pairs
Physical Review D, 2003
Overview of the KEKB accelerators
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2003
The Belle detector
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2002
Search for hadronic b→u decays
Physics Letters B, 1990
CP-Violation in the Renormalizable Theory of Weak Interaction
Progress of Theoretical Physics, 1973
Unitary Symmetry and Leptonic Decays
Physical Review Letters, 1963