90 research outputs found

    The Supersymmetric Flavor Problem for Heavy First-Two Generation Scalars at Next-to-Leading Order

    Get PDF
    We analyze in detail the constraints on SUSY-model parameters obtained from K-Kbar mixing in the hypothesis of a splitted SUSY spectrum. FCNC contributions from gluino-squark-quark interactions are studied in the so-called mass insertion approximation. We present boundaries on mass insertions and on SUSY mass scales. We improve previous results by including the NLO-QCD corrections to Delta S=2 effective Hamiltonian and the complete set of B-parameters for the evaluation of hadronic matrix elements. A full set of magic-numbers, that can be used for further analyses of these models, is also given. We find that the inclusion of NLO-QCD corrections and the B-parameters change the results obtained at LO and in the Vacuum Insertion Approximation by an amount of about 25-35%.Comment: 22 Latex pages, 5 figures; Figs. 1,2 redrawn for K=0.22, section 4.1 revisited, references corrected. Submitted to European Journal of Physics

    The T-Wilson Line

    Full text link
    We argue that soft-collinear effective theory, as is currently formulated, lacks an ingredient which is essential for obtaining a gauge invariant definitions of certain non-perturbative matrix elements relevant for semi-inclusive high-energy processes. Those processes and the companion cross-sections are to be analyzed and measured at the Large Hadron Collider. The missing feature is a gauge link constructed only from the transverse component of the gluon field denoted by the "TT-Wilson line"'. It is neither soft nor collinear. As such it is a new feature of the theory.Comment: 4 pages. To appear in the proceedings of "Quark Confinement and Hadron Nuclei", Madrid 201

    A short review on recent developments in TMD factorization and implementation

    Get PDF
    In the latest years the theoretical and phenomenological advances in the factorization of several collider processes using the transverse momentum dependent distributions (TMD)has greatly increased. I attempt here a short resume of the newest developments discussing also the most recent perturbative QCD calculations. The work is not strictly directed to experts in the field and it wants to offer an overview of the tools and concepts which are behind the TMD factorization and evolution. I consider both theoretical and phenomenological aspects, some of which have still to be fully explored. It is expected that actual colliders and the Electron Ion Collider (EIC) will provide important information in this respect.Comment: Prepared for the Special Issue "Transverse Momentum Dependent Observables from Low to High Energy: Factorization, Evolution, and Global Analyses" which will be published in Advances in High Energy Physic
    • …
    corecore