No abstract available

[en] We compute the QCD corrections at next-to-leading order to the effective Hamiltonian for BB-bar and KK-bar mixing in the Minimal Supersymmetric Standard Model with minimal flavour violation. We take into account the region of low tanβ and focus on QCD corrections to the box diagrams mediated by one additional gluon

[en] A method is suggested to combine tree level QCD matrix for the production of multi jet final states and the parton shower in hadronic interactions. (author)

[en] In this talk, several aspects of high-Q² physics at the LHC are reviewed, with special emphasis on QCD, summarized as follows; (1) Most probably, the success of LHC probably depends on a detailed understanding of QCD; (2) Especially in the first years of LHC running QCD issues will be central, rendering it a great time for QCD-lovers; (3) Apparently, there is considerable leeway for an improved under-standing of QCD - on all levels between theory and experiment (4) There are still puzzles and problems to be resolved, reaching from technicalities (sufficient precision in PDFs, jets and their definitions, multijets, ...) to basis (underlying event, interplay of soft and hard QCD...). (author)

[en] During growth on L-cysteine ethylester, Chlorella fusca (211-8b) accumulated a substance which contained bound sulfide, which could be liberated by reduction with dithioerythritol (DTE) as inorganic sulfide. This substance was extracted with hot methanol and purified by thin layer chromatography. This substance liberated free sulfide when incubated with mono- and dithiols, and thiocyanate was formed after heating with KCN. The isolated substance cochromatographed with authentic sulfur flower using different solvent systems for thin layer chromatography, high pressure liquid chromatography, and the identical spectrum with a relative βmax at 263 nm was found. The chemical structure was confirmed by mass spectrometry showing a molecular weight of 256 m/e for the S₈ configuration. No labeled elemental sulfur was detected when the cells were grown on [³⁵S]sulfate and L-cysteine ethylester. C. fusca seems to have enzymes for the metabolism of elemental sulfur, since it disappeared after prolonged growth into the stationary phase. Cysteine was formed from O-acetyl-L-serine and elemental sulfur in the presence of thiol groups and purified cysteine synthase from spinach or Chlorella

[en] We discuss the possibility that mass effects, beyond phase space, may have substantial influence on the direct determination of V_tq in decays of top quarks. In principle, our considerations are valid both for singly produced top and for tt-bar pair production. The mass effect is practically irrelevant for the extraction of V_tb from Fermilab Tevatron data, but it may have implications for higher energy multijet top decay

No abstract available

[en] We present a calculation of the B⁰ B⁰ mixing including next-to-leading order (NLO) QCD corrections within the two-Higgs doublet model (2HDM). The QCD corrections at NLO are contained in the factor denoted by η₂ which modifies the result obtained at the lowest order of perturbation theory. In the Standard Model case, we confirm the results for η₂ obtained by Buras, Jamin and Weisz (1990). The factor η₂ is gauge and renormalization prescription invariant and it does not depend on the infrared behaviour of the theory, which constitutes an important test of the calculations. The NLO calculations within the 2HDM enhance the LO result up to 18%, which affects the correlation between M_H and V_td. (orig.)

[en] The new multipurpose event-generation framework SHERPA, acronym for Simulation for High-Energy Reactions of PArticles, is presented. It is entirely written in the object-oriented programming language C++. In its current form, it is able to completely simulate electron-positron and unresolved photon-photon collisions at high energies. Also, fully hadronic collisions, such as, e.g., proton-anti-proton, proton-proton, or resolved photon-photon reactions, can be described on the signal level. (author)

No abstract available