The shape of the hadronic form factor f + ( q 2 ) in the decay D 0 → K − e + ν e has been measured in a model independent analysis and compared with theoretical calculations. We use 75 fb − 1 of ...data recorded by the BABAR detector at the PEP-II electron-positron collider. The corresponding decay branching fraction, relative to the decay D 0 → K − π + , has also been measured to be R D = B ( D 0 → K − e + ν e ( γ ) ) / B ( D 0 → K − π + ( γ ) ) = 0.927 ± 0.007 ± 0.012 . From these results, and using the present world average value for B ( D 0 → K − π + ) , the normalization of the form factor at q 2 = 0 is determined to be f + ( 0 ) = 0.727 ± 0.007 ± 0.005 ± 0.007 where the uncertainties are statistical, systematic, and from external inputs, respectively.
A Dalitz plot analysis of approximately 13 000 D + s decays to π + π − π + has been performed. The analysis uses a 384 fb − 1 data sample recorded by the BABAR detector at the PEP-II ...asymmetric-energy e + e − storage ring running at center of mass energies near 10.6 GeV. Amplitudes and phases of the intermediate resonances which contribute to this final state are measured. A high precision measurement of the ratio of branching fractions is performed: B ( D + s → π + π − π + ) / B ( D + s → K + K − π + ) = 0.199 ± 0.004 ± 0.009 . Using a model-independent partial wave analysis, the amplitude and phase of the S wave have been measured.
We present a combined measurement of the Cabibbo-Kobayashi-Maskawa matrix element | V c b | and of the parameters ρ 2 , R 1 ( 1 ) , and R 2 ( 1 ) , which fully characterize the form factors for the B ...0 → D * − ℓ + ν ℓ decay in the framework of heavy-quark effective field theory. The results, based on a selected sample of about 52 800 B 0 → D * − ℓ + ν ℓ decays, recorded by the BABAR detector, are ρ 2 = 1.157 ± 0.094 ± 0.027 , R 1 ( 1 ) = 1.327 ± 0.131 ± 0.043 , R 2 ( 1 ) = 0.859 ± 0.077 ± 0.021 , and F ( 1 ) | V c b | = ( 34.7 ± 0.4 ± 1.0 ) × 10 − 3 . The first error is the statistical and the second is the systematic uncertainty. Combining these measurements with the previous BABAR measurement of the form factors, which employs a different fit technique on a partial sample of the data, we improve the statistical precision of the result, ρ 2 = 1.191 ± 0.048 ± 0.028 , R 1 ( 1 ) = 1.429 ± 0.061 ± 0.044 , R 2 ( 1 ) = 0.827 ± 0.038 ± 0.022 , and F ( 1 ) | V c b | = ( 34.4 ± 0.3 ± 1.1 ) × 10 − 3 . Using lattice calculations for the axial form factor F ( 1 ) , we extract | V c b | = ( 37.4 ± 0.3 ± 1.2 ± 1.2 1.4 ) × 10 − 3 , where the third error is due to the uncertainty in F ( 1 ) . We also present a measurement of the exclusive branching fraction, B = ( 4.69 ± 0.04 ± 0.34 ) % .
A new smelting technology for IIIX15CΓ-B electrosteel is described. In this technology, the steel undergoes treatment in a ladle-furnace unit and a vacuum system. The output of bar batches of all ...five size groups is analyzed for the content of nonmetallic inclusions according to State Standard GOST 801-78 and the ASTM E-45 standard (method A). The phase-mineral composition of furnace slag on smelting steel in a DSP-60 arc furnace is studied by X-ray microstructural analysis. The change in chemical composition of oxide-fluoride slag when the steel passes through the ladle-furnace unit and the vacuum system is analyzed, along with the influence of CaF^sub 2^ on the activity of FeO in oxide-fluoride slag and on the durability of the ladle lining. In conclusion, the need for environmental improvements is noted, in the light of the use of fluorspar; research into means of reducing fluorspar consumption must be activated.PUBLICATION ABSTRACT
We search for the decay Υ ( 1 S ) → γ A 0 , A 0 → g g or s ¯ s , where A 0 is the pseudoscalar light Higgs boson predicted by the next-to-minimal supersymmetric Standard Model. We use a sample of ( ...17.6 ± 0.3 ) × 10 6 Υ ( 1 S ) mesons produced in the BABAR experiment via e + e − → Υ ( 2 S ) → π + π − Υ ( 1 S ) . We see no significant signal and set 90%-confidence-level upper limits on the product branching fraction B ( Υ ( 1 S ) → γ A 0 ) ⋅ B ( A 0 → g g or s ¯ s ) ranging from 10 − 6 to 10 − 2 for A 0 masses in the range 0.5 - 9.0 GeV / c 2 .
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