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QCD Corrections to Photon Production in Association with Hadrons in $e^+e^-$ Annihilation

Zoltan Kunszt·Zoltán Trócsányi
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Abstract

A detailed investigation of the theoretical ambiguities present in the QCD description of photon production in $e^+e^-$ annihilation is given. It is pointed out that in a well-defined perturbative analysis it is necessary to subtract the quark-photon collinear singularities. This subtraction requires the introduction of an unphysical parameter in the perturbative part of the cross section. The subtracted term is factored into non-perturbative fragmentation function. The dependence on the unphysical parameter cancels in the sum of non-perturbative and perturbative parts. It is pointed out that for $E_γ\le \sqrt{s}/(2(1+ε_c))$ the non-perturbative contributions are suppressed. Using a general purpose next-to-leading order Monte Carlo program, we calculate various physical quantities that were measured in LEP experiments recently.

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Zoltan Kunszt, Zoltán Trócsányi. 1992-07-10. QCD Corrections to Photon Production in Association with Hadrons in $e^+e^-$ Annihilation. https://doi.org/10.1016/0550-3213(93)90104-w

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