Observation of the Decay B0 => rho+ rho- and Measurement of the Branching Fraction and Polarization

Abstract

We have observed the rare decay B0 => rho+ rho- in a sample of 89 million BB pairs recorded with the BABAR detector. The number of observed events is 88 +23-21 +-9, with a significance of 5.1 standard deviations with systematic uncertainties included. The branching fraction and the longitudinal polarization are measured to be BR(B0 => rho+ rho-) = (25 +7-6 +5-6)*10^{-6} and Gamma_L/Gamma = 0.98 +0.02-0.08 +-0.03, respectively.

arXiv comment8 pages, 3 postscript figues, submitted to Phys. Rev. D (Rapid Communications)

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Cited by in corpus (24)

• Final State Interactions in Hadronic B Decays
• B -> M1 M2: Factorization, Charming Penguins, Strong Phases, and Polarization
• Polarizations in B -> VV decays
• The Riddle of Polarization in $B\to VV$ Transitions
• Final state interactions for B => VV charmless decays
• Data for Polarization in Charmless B -> phi K^*: A Signal for New Physics?
• Isospin-breaking effects on alpha extracted in B --> pi pi, rho rho, rho pi
• Polarizations in decays B_{u,d}\to VV and possible implications for R-parity violating SUSY
• Study of the decay B0(B0bar)-->rho+rho-, and constraints on the CKM angle alpha
• The $b\to s$ penguin amplitude in charmless $B\to PP$ decays
• Improved Measurement of the CKM Angle alpha Using B0->rho+rho- Decays
• Branching Ratio and Polarization of $B\to \rho (\omega )\rho (\omega )$ Decays in Perturbative QCD Approach
• On measuring alpha in B(t)-> rho^\pm pi^\mp
• Expectations on $B\to (K_0^{\ast }(1430),K_2^{\ast }(1430))\varphi$ decays
• Limit on the B0->rho0rho0 Branching Fraction and Implications for the CKM Angle alpha
• Measurement of Branching Fraction and CP Asymmetry in B+ ->rho+ pi0
• B Meson Decays to mega K*, omega rho, omega omega, omega phi, and omega f0
• Evidence for B0->rho0rho0 Decay and Implications for the CKM Angle alpha
• First measurement of polarizations in the decay $D^0\to \omega \varphi$
• CP violation in B meson decays
• Measurements of B meson decays to omega K* and omega rho
• Baryon helicity in B decay
• Constraints upon the CKM angle phi_2 (alpha) from Belle and BaBar
• Selected Topics in CP Violation and Weak Decays from BABAR