On the lowest order electroweak corrections to spin-12 fermion scattering: (I). The one-loop diagrammar

Based on a gauge model of the electroweak interaction the total set of all one-loop diagrams for scattering of $\text{spin}\text{-}\text{1}\text{2}$ fermions is calculated. Throughout the calculations, the type of fermions (?, ν, …) and of heavy vector bosons (W^±Z⁰, …) is not specified. Derivation of finite parts of each diagram is carried out under the restriction that all invariants of the amplitude are much larger than all fermion masses squared. This allows us to use the expression obtained at arbitrary high energies where weak and electromagnetic interaction strengths are comparable.     

On kaon production in e<Superscript>+</Superscript>e<Superscript>-</Superscript> and semi-inclusive DIS reactions

We consider semi-inclusive unpolarized DIS for the production of charged kaons and the different possibilities to test the conventionally used assumptions s-s̄=0 and D_d ^K+-K-=0. The tests considered have the advantage that they do not require any knowledge of the fragmentation functions. We also show that measurements of both charged and neutral kaons would allow for the determination of the kaon fragmentation functions D_q ^K++K- solely from SIDIS measurements, and we discuss the comparison of (D_u-D_d)^K+-K- obtained independently in SIDIS and e⁺e^- reactions. All analyses are performed in LO and NLO in QCD. The feasibility of the tests to HERMES SIDIS data is considered. PACS 12.38.Bx; 13.85.Ni     

Atomic parity-violation and precision physics

The atomic parity-violation (APV) parameter for a nucleus with n neutrons and z protons has been included in the list of pseudo-observables accessible with the codes TOPAZ0 and ZFITTER. In this way one can add the APV results in the LEP EWWG “global” electroweak fits, checking the corresponding effect when added to the existing precision measurements. Received: 8 March 2001 / Published online: 21 September 2001     

The rate difference between the weak decays of t and in supersymmetry

We find that the CP-violating asymmetry

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at the one-loop order within the minimal supersymmetric extension of the standard model is of the order of few percent for maximal CP violation. It could be measured by considering the rate difference in the one-lepton events.     

Sur le comportement rhéologique des résines thermoréactives durcies et chargées

Sans résuméAvec 7 figures     

SANCnews: Top decays in QCD and EW sectors

In this paper we present the results of the implementation of the decay t → bf ₁ $ \bar f $ \bar f ′₁ into the SANC system (f ₁ is a massless fermion). The new aspect of the work is the combination of QCD and EW corrections. All calculations are done at the one-loop level in the Standard Model. We give a detailed account of the new procedure — the forming of a class of J _{AW, WA} functions. These functions are related to the procedure of extraction of infrared and mass-shell singular divergences. The emphasis of this paper is on the presentation of numerical results for various approaches: complete one-loop calculations and different versions of pole approximations.     

Update of the MCSANC Monte Carlo integrator,v. 1.20

New features of the MCSANC v.1.20 program, a Monte Carlo tool for calculation of the next-to-leading order electroweak and QCD corrections to various Standard Model processes, have been presented. The extensions concern implementation of Drell–Yan-like processes and include a systematic treatment of the photon-induced contribution in proton–proton collisions and electroweak corrections beyond the NLO approximation. There are also technical improvements such as calculation of the forward–backward asymmetry for the neutral current Drell–Yan process. The updated code is suitable for studies of the effects due to EW and QCD radiative corrections to Drell–Yan (and several other) processes at the LHC and for forthcoming high-energy proton–proton colliders.