Abstract: We study the process gamma gamma -> J/psi omega using a data sample of 519.2 fb(-1) recorded by the BABAR detector at SLAC at the PEP-II asymmetric-energy e(+)e(-) collider at center-of-mass energies near the gamma(nS) (n = 2, 3, 4) resonances. We confirm the existence of the charmoniumlike resonance X (3915) decaying to J/psi omega with a significance of 7.6 standard deviations, including systematic uncertainties, and measure its mass (3919.4 +/- 2.2 +/- 1.6) MeV/c(2) and width (13 +/- 6 +/- 3) MeV, where the first uncertainty is statistical and the second systematic. A spin-parity analysis supports the assignment J(P) = 0(+) and therefore the identification of the signal as due to the chi(c0)(2P) resonance. In this hypothesis we determine the product between the two-photon width and the final state branching fraction to be (52 +/- 10 +/- 3) eV.

Abstract: A search for the decay B-s(0) -> D*(-/+)pi(+/-) is presented using a data sample corresponding to an integrated luminosity of 1.0 fb(-1) of pp collisions collected by LHCb. This decay is expected to be mediated by a W-exchange diagram, with little contribution from rescattering processes, and therefore a measurement of the branching fraction will help us to understand the mechanism behind related decays such as B-s(0) -> pi(+)pi(-) and B-s(0) -> D (D) over bar. Systematic uncertainties are minimized by using B-0 -> D*(-/+)pi(+/-) as a normalization channel. We find no evidence for a signal, and set an upper limit on the branching fraction of B(B-s(0) -> D*(-/+)pi(+/-) < 6.1(7.8) x 10(-6) at 90% (95%) confidence level.

Abstract: We report a measurement of the branching fraction of the exclusive charmless semileptonic decay B+ -> omega l(+) nu, where l is either an electron or amuon. We use samples of B+ mesons tagged by a reconstructed charmed semileptonic decay of the other B meson in the event. The measurement is based on a data set of 426.1 fb(-1) of e(+)e(-) collisions at a center-of-mass energy of 10.58 GeV recorded with the BABAR detector at the PEP-II asymmetric-energy e(+)e(-) storage rings. We measure a branching fraction of B(B+ -> omega l(+) nu) = (1.35 +/- 0.21 +/- 0.11) x 10(-4), where the uncertainties are statistical and systematic, respectively. We also present measurements of the partial branching fractions in three bins of q(2), the invariant-mass squared of the lepton-neutrino system, and we compare them to theoretical predictions of the form factors.

Abstract: Based on the full BABAR data sample, we report improved measurements of the ratios R(D) = B((B) over bar -> D tau(-)(v) over bar (tau))/B((B) over bar -> Dl(-)(v) over bar (l)) and R(D*) = B((B) over bar -> D*tau(-)(v) over bar (tau))/B((B) over bar -> D*l(-)(v) over bar (l)), where l refers to either an electron or muon. These ratios are sensitive to new physics contributions in the form of a charged Higgs boson. We measure R(D) = 0.440 +/- 0.058 +/- 0.042 and R(D*) = 0.332 +/- 0.024 +/- 0.018, which exceed the standard model expectations by 2.0 sigma and 2.7 sigma, respectively. Taken together, the results disagree with these expectations at the 3.4 sigma level. This excess cannot be explained by a charged Higgs boson in the type II two-Higgs-doublet model. Kinematic distributions presented here exclude large portions of the more general type III two-Higgs-doublet model, but there are solutions within this model compatible with the results.

Abstract: The e(+)e(-) -> p (p) over bar cross section and the proton magnetic form factor have been measured in the center-of-mass energy range from 3.0 to 6.5 GeV using the initial-state radiation technique with an undetected photon. This is the first measurement of the form factor at energies higher than 4.5 GeV. The analysis is based on 469 fb-1 of integrated luminosity collected with the BABAR detector at the PEP-II collider at e(+)e(-) center-of-mass energies near 10.6 GeV. The branching fractions for the decays J/psi -> p (p) over bar and psi(2S) -> p (p) over bar have also been measured.