Gluon fragmentation into quarkonium at next-to-leading order

Open Access
Regular Article - Theoretical Physics

Abstract

We present the first calculation at next-to-leading order (NLO) in α s of a fragmentation function into quarkonium whose form at leading order is a nontrivial function of z, namely the fragmentation function for a gluon into a spin-singlet S-wave state at leading order in the relative velocity. To calculate the real NLO corrections, we introduce a new subtraction scheme that allows the phase-space integrals to be evaluated in 4 dimensions. We extract all ultraviolet and infrared divergences in the real NLO corrections analytically by calculating the phase-space integrals of the subtraction terms in 4 − 2ϵ dimensions. We also extract the divergences in the virtual NLO corrections analytically, and detail the cancellation of all divergences after renormalization. The NLO corrections have a dramatic effect on the shape of the fragmentation function, and they significantly increase the fragmentation probability.

Keywords

NLO Computations QCD Phenomenology 

Notes

Open Access

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Copyright information

© The Author(s) 2015

Authors and Affiliations

  1. 1.Centre for Cosmology, Particle Physics and Phenomenology (CP3)Université catholique de Louvain, Chemin du Cyclotron 2Louvain-la-NeuveBelgium
  2. 2.Department of PhysicsThe Ohio State UniversityColumbusUnited States

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