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Threshold expansion of massive coloured particle cross sections

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 نشر من قبل Martin Beneke
 تاريخ النشر 2010
  مجال البحث
والبحث باللغة English
 تأليف M. Beneke




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Pair production of massive coloured particles in hadron collisions is accompanied by potentially large radiative corrections related to the suppression of soft gluon emission and enhanced Coulomb exchange near the production threshold. We recently developed a framework to sum both series of corrections for the partonic cross section using soft-collinear and non-relativistic effective theory. If it can be argued that the resummed cross section approximates the complete result over a significant kinematic range, an improvement of the hadronic cross section results, even when the production is not kinematically constrained to the threshold. This is discussed here for the case of top quark production.



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