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A comment on form factor mass singularities in flavor-changing neutral currents

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Zeitschrift für Physik C Particles and Fields

Abstract

Flavor-changing effective verticesq l q h V 0, whereV 0 represents a neutral gauge boson (γ,Z 0,g), involving a heavy external quark, are discussed within the standard model at one-loop level and second-order approximation in external momenta and masses: the logarithmic singular terms in the form factors at vanishing mass of the internal quark in the loop have to be replaced by pieces coming from next order in external momenta. Implications in theb→d+X penguin transitions are commented.

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Authors and Affiliations

  1. Departmento de Física Teórica and Instituto de Fisica corpuscular (IFIC), Centro Mixto Universidad de Valencia-CSIC, Dr. Moliner 50, E-46100, Burjassot, Valencia, Spain

    M. A. Sanchis

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Sanchis, M.A. A comment on form factor mass singularities in flavor-changing neutral currents. Z. Phys. C - Particles and Fields 52, 511–515 (1991). https://doi.org/10.1007/BF01559448

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  • DOI: https://doi.org/10.1007/BF01559448

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