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C. Diaconu

Publications and source records attributed to C. Diaconu.

23 records · Page 2Linked to original sources

Parton distribution functions at LO, NLO and NNLO with correlated uncertainties between orders

Sets of parton distribution functions (PDFs) of the proton are reported for the leading (LO), next-to-leading (NLO) and next-to-next-to leading order (NNLO) QCD calculations. The parton distribution functions are determined with the HERAFitter program using the data from the HERA experiments and preserving correlations between uncertainties for the LO, NLO and NNLO PDF sets. The sets are used to study cross-section ratios and their uncertainties when calculated at different orders in QCD. A reduction of the overall theoretical uncertainty is observed if correlations between the PDF sets are taken into account for the ratio of $WW$ di-boson to $Z$ boson production cross sections at the LHC.

hep-ph↗

Isolated Lepton Production at Colliders

The production of isolated leptons with high transverse momentum in high energy e-e, p-p or e-p collisions is reviewed. The leptons are produced either through boson splitting or by boson-boson collision and yield experimentally simple and spectacular topologies which can be exploited to validate the Standard Model or to search for new phenomena.

hep-ph↗

High P_T Leptons and W Production at HERA

Details are given of the observation by H1 of events containing high P_T leptons in addition to large missing P_T. A closely related ZEUS analysis, including a preliminary measurement of the W production cross section, is discussed and the two experiments are compared. Some possible non-Standard Model sources for the events are considered.

hep-ph↗

Improved variables for measuring the $Lambda_b$ polarization

We discuss a few possible strategies for measuring the polarization of the $Λ_{\mathrm{b}}$ baryons produced in $e^+e^-$-annihilation at the $\mathrm{Z}$ resonance through their inclusive semileptonic decays. After reviewing the existing methods, a new method is proposed, based on the ratio of the averages of the squared electron and neutrino energy, including both perturbative and nonperturbative corrections. This variable minimizes the statistical error on the $Λ_{\mathrm{b}}$ polarization, while keeping the systematic theoretical errors at the level of 1-2%. A number of other polarization-sensitive variables are also discussed, such as averages of ratios of the electron and neutrino energy and the distribution in the difference of the electron and neutrino rapidities.

hep-ph↗