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Nonrelativistic QCD for coloured scalar fields

Andre Hoang·Pedro Ruiz-Femenia
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Abstract

We present an effective field theory suitable to describe a non-relativistic particle-antiparticle pair of heavy scalars based on the gauge group SU(3). Its formulation is analogous to that of "velocity NRQCD" (vNRQCD), a non-relativistic effective theory for heavy quark pairs. The matching conditions with scalar QCD and the renormalization group evolution of the effective theory are discussed. The non-relativistic framework proposed here suffices to compute scalar-antiscalar bound state energies at next-to-next-to-leading-logarithmic (NNLL) order and next-to-leading-logarithmic (NLL) threshold production of squarks in $e^+e^-$ and $γγ$ collisions, in particular of the lighter scalar top quark at a future Linear Collider.

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Andre Hoang, Pedro Ruiz-Femenia. 2005-12-13. Nonrelativistic QCD for coloured scalar fields. https://arxiv.org/abs/hep-ph/0512165

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