Using the entire BaBar Υ(4S) data set, the first two-dimensional unbinned angular analysis of the semileptonic decay B→ D ℓ^- ν_ℓ is performed, employing hadronic reconstruction of the tag-side B meson from Υ(4S)→ BB. Here, ℓ denotes the light charged leptons e and μ. A novel data-driven signal-background separation procedure with minimal dependence on simulation is developed. This procedure preserves all multi-dimensional correlations present in the data. The expected sin^2θ_ℓ dependence of the differential decay rate in the Standard Model is demonstrated, where θ_ℓ is the lepton helicity angle. Including input from the latest lattice QCD calculations and previously available experimental data, the underlying form factors are extracted using both model-independent (BGL) and dependent (CLN) methods. Comparisons with lattice calculations show flavor SU(3) symmetry to be a good approximation in the B_(s)→ D_(s) sector. Using the BGL results, the CKM matrix element |V_cb|=(41.09± 1.16)× 10^-3 and the Standard Model prediction of the lepton-flavor universality violation variable ℛ(D)=0.300± 0.004, are extracted. The value of |V_cb| from B→ D ℓ^- ν_ℓ tends to be higher than that extracted using B→ D ℓ^- ν_ℓ. The Standard Model ℛ(D) calculation is at a 1.97σ tension with the latest HFLAV experimental average.

We present a search for seven lepton-flavor-violating neutral charm decays of the type D^0→ X^0 e^±μ^∓, where X^0 represents a π^0, K^0_ S, K̅^̅*̅0̅, ρ^0, ϕ, ω, or η meson. The analysis is based on 468 fb^-1 of e^+e^- annihilation data collected at or close to the Υ(4S) resonance with the BaBar detector at the SLAC National Accelerator Laboratory. No significant signals are observed, and we establish 90% confidence level upper limits on the branching fractions in the range (5.0 - 22.5)× 10^-7. The limits are between one and two orders of magnitude more stringent than previous measurements.

We report the observation of the baryonic decay B̅^0 →Λ^+_c p̅ K^- K^+ using a data sample of 471 × 10^6 BB̅ pairs produced in e^+e^- annihilations at √(s)=10.58 GeV. This data sample was recorded with the BABAR detector at the PEP-II storage ring at SLAC. We find B(B̅^0 →Λ^+_c p̅ K^- K^+ ) = (2.5 ± 0.4_(stat)± 0.2_(syst)± 0.6_ B(Λ^+_c)) × 10^-5, where the uncertainties are statistical, systematic, and due to the uncertainty of the Λ^+_c → p K^- π^+ branching fraction, respectively. The result has a significance corresponding to 5.0 standard deviations, including all uncertainties. For the resonant decay B̅^0 →Λ^+_c p̅ϕ, we determine the upper limit B(B̅^0 →Λ^+_c p̅ϕ) <1.2 × 10^-5 at 90% confidence level.

The Dalitz-plot of the Decay D0 --> pi+ pi- pi0 measured by the BABAR Collaboration shows the structure of a final state having quantum numbers IG JPC = 0- 0--. An isospin analysis of the Daliz-plot finds that the I = 0 contribution is about 96%. This high I = 0 contribution is unexpected because the weak interaction violates the isospin.

We present a preliminary measurement of the time-dependent CP asymmetry in B0 --> K*0 (K_S0 pi0) gamma decays based on 431 x 10^6 Upsilon(4S) --> BBbar decays collected with the BaBar detector at the PEP-II asymmetric-energy e+e- collider at SLAC. In a sample containing 316 +/- 22 signal events we measure S_{K* gamma} = -0.08 +/- 0.31 +/- 0.05 and C_{K* gamma} = -0.15 +/- 0.17 +/- 0.03. The uncertainties are statistical and systematic, respectively.

We present the new and updated BABAR measurements of CP-violation studies for many b{yields}s penguin decay modes. We report the first observation of mixing-induced CP-violation in B{sup 0}{yields}{eta}{prime}K{sup 0} with a significance (including systematic uncertainties) of 5.5{sigma}. We also present the first observation of the decay B{sup 0} {yields} {rho}{sup 0}K{sup 0}. Using the time-dependent Dalitz plot analysis of B{sup 0} {yields} K{sup +}K{sup -}K{sup 0} decay, the CP-parameters A{sub CP} and {beta}{sub eff} are measured with 4.8{sigma} significance, and we reject the solution near {pi}/2 -- {beta}{sub eff} at 4.5 {sigma}. We also present the update measurements of CP-violating parameters for B{sup 0} {yields} K{sup 0}{sub S}{pi}{sup 0}, K{sup 0}{sub S}K{sup 0}{sub S}K{sup 0}{sub S} and {pi}{sup 0}{pi}{sup 0}K{sup 0}{sub S} decays. An updated measurements of the CP-violating charge asymmetries for B{sup {+-}} {yields} {eta}{prime}K{sup {+-}}, {eta}K{sup {+-}} {omega}{eta}K{sup {+-}} decays are also presented. The measurements are based on the data sample recorded at the {Upsilon}(4S) resonance with BABAR detector at the PEP-II B-meson Factory at SLAC.

We report preliminary results of a search for CPT and Lorentz violation in B0-B0bar oscillations using an inclusive dilepton sample collected by the BABAR experiment at the PEP-II B Factory. Using a sample of 232 million BBbar pairs, we search for time-dependent variations in the complex CPT parameter z = z0 + z1*cos(Omega*t^ + phi) where Omega is the Earth's sidereal frequency and t^ is sidereal time. We measure Im(z0) = (-14.1 +- 7.3(stat) +- 2.4(syst)) x 10E-3, DeltaGamma*Re(z0) = (-7.2 +- 4.1(stat) +- 2.1(syst)) x 10E-3 ps-1, Im(z1) = (-24.0 +- 10.7(stat) +- 5.9(syst)) x 10E-3, and DeltaGamma*Re(z1) = (-18.8 +- 5.5(stat) +- 4.0(syst)) x 10E-3 ps-1, where DeltaGamma is the difference between the decay rates of the neutral B mass eigenstates. The statistical correlation between the measurements of Im(z0) and DeltaGamma*Re(z0) is 76%; between Im(z1) and DeltaGamma*Re(z1) it is 79%. These results are used to evaluate expressions involving coefficients for Lorentz and CPT violation in the general Lorentz-violating standard-model extension. In a complementary approach, we examine the spectral power of periodic variations in z over a wide range of frequencies and find no significant signal.

Using 385 fb^-1 of e^+e^- collisions at the CM energies of around 10.6 GeV recorded by the BaBar experiment, we study the amplitudes of the singly Cabibbo-suppressed decay D^0 –> K^- K^+ pi^0. We measure the strong phase difference between the D0bar and D0 decays to the K^*(892)^+ K^- state to be -35.5 +/- 1.9 (stat) +/- 2.2 (syst) degrees, and their amplitude ratio to be 0.599 +/- 0.013 (stat) +/- 0.011 (syst). We observe significant contributions from the Kpi and K^-K^+ scalar and vector amplitudes, and analyze the moments of the cosine of the helicity angle in these systems. We find no evidence for charged, scalar kappa(800) state, nor for higher spin states. We also perform a model-independent partial wave analysis of the K^-K^+ system in a limited mass range around 1 GeV/c^2. We study several models for Kpi S-wave amplitude, and describe which one is favored by our data.

Using 232 fb-1 of data collected by the BABAR detector, the Xic'+ and Xic'0 baryons are reconstructed through the decays: Xic'+ -> Xic+ gamma and Xic'0 -> Xic0 gamma, where Xic+ -> Xi- pi+ pi+ and Xic0 -> Xi- pi+. By measuring the efficiency-corrected yields in different intervals of the center-of-mass momentum, the production rates from B decays and from the continuum are extracted. For production from B decays, the branching fractions are found to be B(B -> Xic'+ X) x B(Xic+ -> Xi- pi+ pi+) = [ 1.69 +- 0.17 (exp.) +- 0.10 (model) ] x 10^-4 and B(B -> Xic'0 X) x B(Xic0 -> Xi- pi+) = [ 0.67 +- 0.07 (exp.) +- 0.03 (model) ] x 10^-4. For production from the continuum the cross-sections are found to be sigma(e+ e- -> Xic'+ X) x B(Xic+ -> Xi- pi+ pi+) = 141 +- 24 (exp.) +- 19 (model) fb and sigma(e+ e- -> Xic'0 X) x B(Xic0 -> Xi- pi+) = 70 +- 11 (exp.) +- 6 (model) fb. The helicity angle distributions of Xic' decays are studied and found to be consistent with J = 1/2.

We search for rare FCNC charm decays of the form X_c^+→ h^+, where X_c^+ is a charm hadron, h is a pion, kaon or proton, and ℓ^('^) is an electron or a muon. In the pion and kaon modes, we study both D^+ and D_s^+ decays, while in the proton modes we study Λ_c^+ decays. Based on a data sample of 288fb^-1 of e^+e^- collisions collected by BABAR, we set preliminary 90 for the branching fractions of the different decay modes. For most decay modes, our analysis provides a significant improvement over previous results.

We present measurements of the flavor-changing neutral current decays B -> Kl+l- and B -> K*l+l-, where l+l- is either an e+e- or mu+mu- pair. The data sample comprises 229 X 10^6 Y(4S) -> BBbar decays collected with the BaBar detector at the PEP-II e+e- storage ring. We measure the branching fractions BF(B -> Kl+l-) = (0.34 +- 0.07 +- 0.03) X 10^-6 and BF(B -> K*l+l-) = (0.78^{+0.19}_{-0.17} +/- 0.12) X 10^-6, the direct CP asymmetries of these decays, and the relative abundances of decays to electrons and muons.

CP violation in B0B0bar mixing is characterized by the value of the parameter |q/p| being different from 1, and the Standard Model predicts this difference to be smaller than 10^{-3}. We present a measurement of this parameter using a partial reconstruction of one of the B mesons in the semileptonic channel D*- l+ nu_l, where only the hard lepton and the soft pion from the D*- --> D0bar pi- decay are reconstructed. The flavor of the other B is determined by means of lepton tagging. The determination of |q/p| is then performed with a fit to the proper time difference of the two B decays. We use a luminosity of 200.8 fb^-1, collected at the Y(4S) resonance by the BaBar detector at the PEP-II asymmetrical-energy e+e- collider, in the period 1999-2004. We obtain the preliminary result: |q/p| - 1 = (6.5 +/- 3.4(stat.) +/- 2.0(syst.)) x 10^{-3}

We present preliminary results from a search for inclusive charmless B->KX decays. These decays occur dominantly via one-loop b->s penguin transitions, and can provide useful information about these processes. Using a sample of 288.5/fb collected with the BABAR detector at the PEP-II asymmetric-energy e+e- B Factory at SLAC, we search for high-energy kaons recoiling against fully reconstructed B decays. We measure the partial branching fractions for kaons with momentum p*(K)>2.34GeV in the B rest frame, and obtain (in units of 10^-6): B(B->K+X, p*>2.34GeV) = 196^{+37}_{-34}(stat.)^{+31}_{-30}(syst.) and B(B->K0X, p*>2.34GeV) = 154^{+55}_{-48}(stat.)^{+55}_{-41}(syst.) (<266 at 90% C.L.).

We present a preliminary measurement of CP-violation parameters in the decay B0 -> K+K-K0, using approximately 347 million BBbar events collected by the BABAR detector at SLAC. Reconstructing the neutral kaon as KS -> pi+pi-, KS -> pi0pi0, or KL, we analyze the Dalitz plot distribution and measure fractions to intermediate states. We extract CP parameters from the asymmetries in amplitudes and phases between B0 and B0bar decays across the Dalitz plot. For decays to phiK0, we find beta_eff=0.06 +/- 0.16 +/- 0.05, Acp=-0.18 +/- 0.20 +/- 0.10, where the first uncertainty is statistical and the second one is systematic. For decays to f0K0, we find beta_eff=0.18 +/- 0.19 +/- 0.04, Acp=0.45 +/- 0.28 +/- 0.10. Combining all KKK0 events and taking account of the different CP eigenvalues of the individual Dalitz plot components, we find beta_eff = 0.361 +/- 0.079 +/- 0.037, Acp = -0.034 +/- 0.079 +/- 0.025. The trigonometric reflection at pi/2 - beta_eff is disfavored at 4.6 sigma. We also study angular distributions in B0 -> K+K-KS and B+ -> phi K+ decays and measure the direct CP asymmetry in B+ -> phi K+ decays, Acp = 0.046 +/- 0.046 +/- 0.017.

We present measurements of time-dependent CP-violation asymmetries for the decays B0 to eta'K0. The data sample corresponds to 347 million BBbar pairs produced by e+e- annihilation at the Upsilon(4S) resonance in the PEP-II collider, and collected with the BaBar detector. The preliminary results are S = 0.55+/-0.11+/-0.002, and C = -0.15+/-0.07+/-0.03, where the first error quoted is statistical, the second systematic.

A search for the decay B+ -> a0+pi0 with the a0+ decaying to an eta and a pi+ was carried out at the Stanford Linear Accelerator Center using the BABAR detector coupled with the PEP-II collider. The analysis used a data sample comprised of approximately 252 million BBbar pairs collected at the Upsilon(4S) resonance. No signal was observed and a 90% confidence level upper limit on the branching fraction was set at 1.32 x 10^{-6}.

Production and decay of Ω_c^0 baryons is studied with ∼230 fb^-1 of data recorded with the BABAR detector at the PEP-II e^+e^- asymmetric-energy storage ring at SLAC. The Ω_c^0 is reconstructed through its decays into Ω^-π^+, Ω^-π^+π^+π^-, and Ξ^-K^-π^+π^+ final states. The invariant mass spectra are presented and the signal yields are extracted. Ratios of branching fractions are measured relative to the Ω^-π^+ mode B(Ξ^-K^-π^+π^+)/B(Ω^-π^+) = 0.31 ±0.15(stat.) ±0.04(syst.), B(Ω^-π^+π^+π^-)/B(Ω^-π^+) < 0.30 (90 The momentum spectrum (not corrected for efficiency) of Ω_c^0 baryons is extracted from decays into Ω^-π^+, establishing the first observation of Ω_c^0 production from B decays.

We report a Dalitz-plot analysis of the charmless hadronic decays of charged B mesons to the final state K+/- pi-/+ pi+/-. Using a sample of 226.0 +/- 2.5 million BBbar pairs collected by the BaBar detector, we measure the magnitudes and phases of the intermediate resonant and nonresonant amplitudes for both charge conjugate decays. We present measurements of the corresponding branching fractions and their charge asymmetries that supersede those of previous BaBar analyses. We find the charge asymmetries to be consistent with zero.

We present preliminary measurements of the CP asymmetry parameters in B^0 -> K^0_S K^0_S K^0_S decays, reconstructing two of the K^0_S into pi^+pi^- and one into pi^0pi^0. In a sample of 227M $B\bar B$ pairs collected by the BABAR detector at the PEP-II B-Factory at SLAC, we find the CP parameters to be S = -0.25^{+0.68}_{-0.61} (stat) +/- 0.05 (syst) and C = 0.56^{+0.34}_{-0.43} (stat) +/- 0.04 (syst). Combining this result with the previous BABAR measurement, obtained from events with three K^0_S decaying into pi^+pi^-, we get S = -0.63^{+0.32}_{-0.28} (stat) +/- 0.04(syst) C = -0.10 +/- 0.25 (stat) +/- 0.05 (syst)

Charmless semileptonic decays, B̅→ X_u ℓν̅, are studied in a sample of 232 million BB̅ decays recorded with the BaBar detector, in events where the decay of the second B meson is fully reconstructed. Inclusive charmless decays are selected in kinematic regions where the dominant background from semileptonic B decays to charm is reduced by requirements on the hadronic mass M_X and the momentum transfer q^2. The partial branching fraction for B̅→ X_u ℓν̅ decays for M_X<1.7 GeV/c^2 and q^2>8 Gev^2/c^4 is measured to be ΔB(B̅→ X_u ℓν̅) = (0.87 ± 0.09_ stat± 0.09_ sys± 0.01_ th)× 10^-3. The CKM matrix element |V_ub| is determined by using theoretical calculations of phase space acceptances. Theoretical uncertainties in this extrapolation are reduced by using the inclusive b → s γ photon spectrum and moments of the b → c ℓν̅ lepton energy and hadronic invariant mass.