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). 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.
|