|
BABAR Collaboration(Lees, J. P. et al), Martinez-Vidal, F., & Oyanguren, A. (2011). Search for Hadronic Decays of a Light Higgs Boson in the Radiative Decay Gamma -> gamma A(0). Phys. Rev. Lett., 107(22), 221803–7pp.
Abstract: We search for hadronic decays of a light Higgs boson (A(0)) produced in radiative decays of an Gamma(2S) or Gamma(3S) meson, Gamma -> gamma A(0). The data have been recorded by the BABAR experiment at the Gamma(3S) and Gamma(2S) center-of-mass energies and include (121.3 +/- 1.2) x 10(6) Gamma(3S) and (98.3 +/- 0.9) x 10(6) Gamma(2S) mesons. No significant signal is observed. We set 90% confidence level upper limits on the product branching fractions B(Gamma(nS) -> gamma A(0))B(A(0) -> hadrons) (n = 2 or 3) that range from 1 x 10(-6) for an A(0) mass of 0: 3 GeV/c(2) to 8 x 10(-5) at 7 GeV/c(2).
|
|
|
BABAR Collaboration(Lees, J. P. et al), Martinez-Vidal, F., & Oyanguren, A. (2011). Observation of the baryonic B decay (B)over-bar(0) -> Lambda(+)(c)(Lambda)over-barK(-). Phys. Rev. D, 84(7), 071102–7pp.
Abstract: We report the observation of the baryonic B decay (B) over bar (0) -> Lambda(+)(c)Lambda K(-) with a significance larger than 7 standard deviations based on 471 x 10(6) B (B) over bar pairs collected with the BABAR detector at the PEP-II storage ring at SLAC. We measure the branching fraction for the decay (B) over bar (0) -> Lambda(+)(c)Lambda K(-) to be (3.8 +/- 0.8(stat) +/- 0.2(sys) +/- 1.0(Lambda c)(+)) x 10(-5). The uncertainties are statistical, systematic, and due to the uncertainty in the Lambda(+)(c) branching fraction. We find that the Lambda(+)(c)K(-) invariant-mass distribution shows an enhancement above 3.5 GeV/c(2).
|
|
|
BABAR Collaboration(Lees, J. P. et al), Martinez-Vidal, F., & Oyanguren, A. (2011). Branching fraction measurements of the color-suppressed decays B-bar(0) to D((*)0)pi(0), D((*)0)eta, D((*)0)omega, and D((*)0)eta ' and measurement of the polarization in the decay B-bar(0) -> D((*)0)omega. Phys. Rev. D, 84(11), 112007–25pp.
Abstract: We report updated branching fraction measurements of the color-suppressed decays (B) over bar (0) -> D(0)pi(0), D*(0)pi(0), D(0)eta, D*(0)eta, D(0)omega, D*(0)omega, D(0)eta', and D*(0)eta'. We measure the branching fractions (x 10(-4)): B((B) over bar (0) -> D(0)pi(0)) = 2.69 +/- 0.09 +/- 0.13, B((B) over bar (0) -> D(0)pi(0)) = 3.05 +/- 0.14 +/- 0.28, B((B) over bar (0) -> D(0)eta) = 2.53 +/- 0.09 +/- 0.11, B((B) over bar (0) -> D(0)eta) = 2.69 +/- 0.14 +/- 0.23, B((B) over bar (0) -> D(0)eta) = 2.57 +/- 0.11 +/- 0.14, B((B) over bar (0) -> D*(0)omega) = 4.55 +/- 0.24 +/- 0.39, B((B) over bar (0) -> D*(0)omega) = 1.48 +/- 0.13 +/- 0.07, and B((B) over bar (0) -> D*(0)eta') = 1.49 +/- 0.22 +/- 0.15. We also present the first measurement of the longitudinal polarization fraction of the decay channel D*(0)omega, f(L) = (66.5 +/- 4.7 +/- 1.5)%. In the above, the first uncertainty is statistical and the second is systematic. The results are based on a sample of (454 +/- 5) x 10(6) B (B) over bar pairs collected at the Gamma(4S) resonance, with the BABAR detector at the PEP-II storage rings at SLAC. The measurements are the most precise determinations of these quantities from a single experiment. They are compared to theoretical predictions obtained by factorization, Soft Collinear Effective Theory (SCET) and perturbative QCD (pQCD). We find that the presence of final state interactions is favored and the measurements are in better agreement with SCET than with pQCD.
|
|
|
BABAR Collaboration(Lees, J. P. et al), Lopez-March, N., Martinez-Vidal, F., & Oyanguren, A. (2011). Searches for rare or forbidden semileptonic charm decays. Phys. Rev. D, 84(7), 072006–13pp.
Abstract: We present searches for rare or forbidden charm decays of the form X(c)(+) -> h(+/-)l(+/-)l((l)+), where X(c)(+) is a charm hadron (D(+), D(s)(+), or A(c)(+)), h +/- is a pion, kaon, or proton, and l((l)+/-) is an electron or muon. The analysis is based on 384 fb(-1) of e(+)e(-) annihilation data collected at or close to the gamma(4S) resonance with the BABAR detector at the SLAC National Accelerator Laboratory. No significant signal is observed for any of the 35 decay modes that are investigated. We establish 90% confidence-level upper limits on the branching fractions between 1 x 10(-6) and 44 x 10(-6) depending on the channel. In most cases, these results represent either the first limits or significant improvements on existing limits for the decay modes studied.
|
|
|
BABAR Collaboration(Lees, J. P. et al), Martinez-Vidal, F., & Oyanguren, A. (2011). Search for CP violation using T-odd correlations in D(+) -> K(+)K(S)(0) pi(+)pi(-) and D(s)(+) -> K(+)K(S)(0) pi(+)pi(-) decays. Phys. Rev. D, 84(3), 031103–9pp.
Abstract: We search for CP violation in a sample of 20 000 Cabibbo-suppressed decays, D(+) -> K(+)K(S)(0)pi(+)pi(-), and 30 000 Cabibbo-favored decays, D(+) -> K(+)K(S)(0)pi(+)pi(-). We use 520 fb(-1) of data recorded by the BABAR detector at the PEP-II asymmetric-energy e(+)e(-) collider operating at center of mass energies near 10.6 GeV. We search for CP violation in the difference between the T-odd asymmetries obtained using triple product correlations of the D(+)(D(s)(+)) and D(-)(D(s)(-)) decays, respectively. The T violation parameter values obtained are A(T)(D(+)) = (-12.0 +/- 10.0(stat) +/- 4.6(syst)) x 10(-3) and A(T)(D(s)(+)) = (-13.6 +/- 7.7(stat) +/- 3.4(syst)) x 10(-3), which are consistent with the standard model expectations.
|
|