We report a measurement of the branching fractions of B̄→D* *ℓ-ν̄ℓ decays based on 417fb-1 of data collected at the Υ(4S) resonance with the BABAR detector at the PEP-II e+e- storage rings. Events are selected by fully reconstructing one of the B mesons in a hadronic decay mode. A fit to the invariant mass differences m(D(*)π)- m(D(*)) is performed to extract the signal yields of the different D** states. We observe the B̄→D**ℓ- ν̄ℓ decay modes corresponding to the four D** states predicted by heavy quark symmetry with a significance greater than 5 standard deviations including systematic uncertainties. © 2008 The American Physical Society.

A search is presented for the four-body decay B0 → ppp p in a sample of 471 million BB pairs collected with the BABAR detector, operated at the SLAC PEP-II asymmetric-energy e+e- collider. The center-ofmass energy is 10.58 GeV. From a fit to the distribution of the energy-substituted mass mES, the branching fraction B(B0 → ppp p) = (1.1 ± 0.5 ± 0.2) × 10-7 is extracted, where the first uncertainty is statistical and the second is systematic. The significance of the signal, including the systematic uncertainty, is 2.9 standard deviations. The upper limit on the branching fraction is determined to be 2.0 × 10-7 at 90% confidence level.

We study the reaction e+e-→e+e -ηc, ηc→KSK±π" and obtain ηc mass and width values 2982.2±0.4±1.6MeV/c2 and 31.7±1.2±0.8MeV, respectively. We find Γ(ηc→γ γ)B(ηc→KK̄π)=0.374±0.009±0.031keV, and measure the γγ*→ηc transition form factor in the momentum transfer range from 2 to 50GeV2. The analysis is based on 469fb-1 of integrated luminosity collected at PEP-II with the BABAR detector at e+e- center-of-mass energies near 10.6 GeV. © 2010 The American Physical Society.

We present updated measurements of time-dependent CP asymmetries in fully reconstructed neutral B decays containing a charmonium meson. The measurements reported here use a data sample of (465±5)×106 Υ(4S) →BB̄ decays collected with the BABAR detector at the PEP-II asymmetric energy e+e- storage rings operating at the SLAC National Accelerator Laboratory. The time-dependent CP asymmetry parameters measured from JψKS0, JψKL0, ψ(2S)KS0, ηcKS0, χc1KS0, and J/ψK*(892)0 decays are: Cf=0.024±0.020(stat)±0.016(syst) and -ηfSf=0. 687±0.028(stat)±0.012(syst). © 2009 The American Physical Society.

We study the process e+e-→e+e-η′ in the double-tag mode and measure for the first time the γ γ →η′ transition form factor Fη′(Q12,Q22) in the momentum-transfer range 2

We present measurements of the inclusive production of antideuterons in e+e- annihilation into hadrons at ≈10.58GeV center-of-mass energy and in (1S,2S,3S) decays. The results are obtained using data collected by the BABAR detector at the PEP-II electron-positron collider. Assuming a fireball spectral shape for the emitted antideuteron momentum, we find B((1S)→d̄X)=(2. 81±0.49(stat)-0.24+0.20(syst))×10-5, B((2S)→d̄X)=(2. 64±0.11(stat)-0.21+0.26(syst))×10-5, B((3S)→d̄X)=(2. 33±0.15(stat)-0.28+0.31(syst))×10-5, and σ(e+e- →d̄X)=(9.63±0.41(stat)-1.01+1.17(syst)fb. © 2014 American Physical Society.

We measure the mass difference, Δm_{+}, between the D^{*}(2010)^{+} and the D^{+} using the decay chain D^{*}(2010)^{+}→D^{+}π^{0} with D^{+}→K^{-}π^{+}π^{+}. The data were recorded with the BABAR detector at center-of-mass energies at and near the ϒ(4S) resonance, and correspond to an integrated luminosity of approximately 468  fb^{-1}. We measure Δm_{+}=(140 601.0±6.8[stat]±12.9[syst])  keV. We combine this result with a previous BABAR measurement of Δm_{0}≡m(D^{*}(2010)^{+})-m(D^{0}) to obtain Δm_{D}=m(D^{+})-m(D^{0})=(4824.9±6.8[stat]±12.9[syst])  keV. These results are compatible with and approximately five times more precise than the Particle Data Group averages.

We report the observation of the rare charm decay D^{0}→K^{-}π^{+}e^{+}e^{-}, based on 468  fb^{-1} of e^{+}e^{-} annihilation data collected at or close to the center-of-mass energy of the ϒ(4S) resonance with the BABAR detector at the SLAC National Accelerator Laboratory. We find the branching fraction in the invariant mass range 0.675

We describe in detail a previously published measurement of CP violation in B0-B¯0 oscillations, based on an integrated luminosity of 425.7 fb-1 collected by the BABAR experiment at the PEPII collider. We apply a novel technique to a sample of about 6 million B¯0→D∗+-ν¯ decays selected with partial reconstruction of the D∗+ meson. The charged lepton identifies the flavor of one B meson at its decay time, the flavor of the other B is determined by kaon tagging. We determine a CP violating asymmetry ACP=(N(B0B0)-N(B¯0B¯0))/(N(B0B0)+N(B¯0B¯0))=(0.06±0.17-0.32+0.38)% corresponding to ΔCP=1-|q/p|=(0.29±0.84-1.61+1.88)×10-3. This measurement is consistent and competitive with those obtained at the B factories with dilepton events.