MolDynGrid virtual laboratory has been established for collaborative research in computational biology and bioinformatics that requires high processing power and huge storage space. This research ...involves molecular dynamics (MD) simulations of biological macromolecules, such as proteins, nucleic acids and their complexes. Also, a comparison of MD simulation results with experimental NMR spectroscopy data is proposed. The main aim of MolDynGrid virtual laboratory is to provide an efficient infrastructure for automation of MD job processing in Grid. It will assist research workers to use Grid for their needs without having them to be familiar with highly complicated internals of the Grid.
We present measurements of the branching fractions and charge asymmetries of B decays to all D ( * ) ¯¯¯ D ( * ) modes. Using 232 × 10 6 B ¯¯¯ B pairs recorded on the Υ ( 4 S ) resonance by the BABAR ...detector at the e + e − asymmetric B factory PEP-II at the Stanford Linear Accelerator Center, we measure the branching fractions B ( B 0 → D * + D * − ) = ( 8.1 ± 0.6 ± 1.0 ) × 10 − 4 , B ( B 0 → D * ± D ∓ ) = ( 5.7 ± 0.7 ± 0.7 ) × 10 − 4 , B ( B 0 → D + D − ) = ( 2.8 ± 0.4 ± 0.5 ) × 10 − 4 , B ( B + → D * + ¯¯¯ D * 0 ) = ( 8.1 ± 1.2 ± 1.2 ) × 10 − 4 , B ( B + → D * + ¯¯¯ D 0 ) = ( 3.6 ± 0.5 ± 0.4 ) × 10 − 4 , B ( B + → D + ¯¯¯ D * 0 ) = ( 6.3 ± 1.4 ± 1.0 ) × 10 − 4 , and B ( B + → D + ¯¯¯ D 0 ) = ( 3.8 ± 0.6 ± 0.5 ) × 10 − 4 , where in each case the first uncertainty is statistical and the second systematic. We also determine the limits B ( B 0 → D * 0 ¯¯¯ D * 0 ) < 0.9 × 10 − 4 , B ( B 0 → D * 0 ¯¯¯ D 0 ) < 2.9 × 10 − 4 , and B ( B 0 → D 0 ¯¯¯ D 0 ) < 0.6 × 10 − 4 , each at 90% confidence level. All decays above denote either member of a charge-conjugate pair. We also determine the C P -violating charge asymmetries A ( B 0 → D * ± D ∓ ) = 0.03 ± 0.10 ± 0.02 , A ( B + → D * + ¯¯¯ D * 0 ) = − 0.15 ± 0.11 ± 0.02 , A ( B + → D * + ¯¯¯ D 0 ) = − 0.06 ± 0.13 ± 0.02 , A ( B + → D + ¯¯¯ D * 0 ) = 0.13 ± 0.18 ± 0.04 , and A ( B + → D + ¯¯¯ D 0 ) = − 0.13 ± 0.14 ± 0.02 . Additionally, when we combine these results with information from time-dependent C P asymmetries in B 0 → D ( * ) + D ( * ) − decays and world-averaged branching fractions of B decays to D ( * ) s ¯¯¯ D ( * ) modes, we find the Cabibbo-Kobayashi-Maskawa phase γ is favored to lie in the range (0.07-2.77) radians (with a + 0 or + π radians ambiguity) at 68% confidence level.
We present an investigation of the decays ¯¯¯ B 0 → Λ + c ¯ p and B − → Λ + c ¯ p π − based on 383 × 10 6 Υ ( 4 S ) → B ¯¯¯ B decays recorded with the BABAR detector. We measure the branching ...fractions of these decays; their ratio is B ( B − → Λ + c ¯ p π − ) / B ( ¯¯¯ B 0 → Λ + c ¯ p ) = 15.4 ± 1.8 ± 0.3 . The B − → Λ + c ¯ p π − process exhibits an enhancement at the Λ + c ¯ p threshold and is a laboratory for searches for excited charm baryon states. We observe the resonant decays B − → Σ c ( 2455 ) 0 ¯ p and B − → Σ c ( 2800 ) 0 ¯ p but see no evidence for B − → Σ c ( 2520 ) 0 ¯ p . This is the first observation of the decay B − → Σ c ( 2800 ) 0 ¯ p ; however, the mass of the observed excited Σ 0 c state is ( 2846 ± 8 ± 10 ) MeV / c 2 , which is somewhat inconsistent with previous measurements. Finally, we examine the angular distribution of the B − → Σ c ( 2455 ) 0 ¯ p decays and measure the spin of the Σ c ( 2455 ) 0 baryon to be 1 / 2 , as predicted by the quark model.
We present results for a time-dependent Dalitz plot measurement of C P -violating asymmetries in the mode B 0 → π + π − π 0 . The data set is derived from the complete sample of 471 × 10 6 B ¯¯¯ B ...meson pairs collected with the BABAR detector at the PEP-II asymmetric-energy e + e − collider at the SLAC National Accelerator Laboratory operating on the Υ ( 4 S ) resonance. We extract parameters describing the time-dependent B 0 → ρ π decay probabilities and C P asymmetries, including C = 0.016 ± 0.059 ± 0.036 , Δ C = 0.234 ± 0.061 ± 0.048 , S = 0.053 ± 0.081 ± 0.034 , and Δ S = 0.054 ± 0.082 ± 0.039 , where the uncertainties are statistical and systematic, respectively. We perform a two-dimensional likelihood scan of the direct C P -violation asymmetry parameters for B 0 → ρ ± π ∓ decays, finding the change in χ 2 between the minimum and the origin (corresponding to no direct C P violation) to be Δ χ 2 = 6.42 . We present information on the C P -violating parameter α in a likelihood scan that incorporates B ± → ρ π measurements. To aid in the interpretation of our results, statistical robustness studies are performed to assess the reliability with which the true values of the physics parameters can be extracted. Significantly, these studies indicate that α cannot be reliably extracted with our current sample size, though the other physics parameters are robustly extracted.
We establish improved upper limits on branching fractions for B 0 decays to final states where the decay products are purely invisible (i.e., no observable final state particles) and for final states ...where the only visible product is a photon. Within the Standard Model, these decays have branching fractions that are below the current experimental sensitivity, but various models of physics beyond the Standard Model predict significant contributions for these channels. Using 471 × 10 6 B ¯¯¯ B pairs collected at the Υ ( 4 S ) resonance by the BABAR experiment at the PEP-II e + e − storage ring at the SLAC National Accelerator Laboratory, we establish upper limits at the 90% confidence level of 2.4 × 10 − 5 for the branching fraction of B 0 → invisible and 1.7 × 10 − 5 for the branching fraction of B 0 → invisible + γ .
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