Abstract
The sophistication of current predictions for Z+jet production at hadron colliders necessitates a re-evaluation of any approximations inherent in the theoretical calculations. In this paper we address one such issue, the inclusion of mass effects in top-quark loops. We ameliorate an existing calculation of Z + 1 jet and Z + 2 jet production by presenting exact analytic formulae for amplitudes containing top-quark loops that enter at next-to-leading order in QCD. Although approximations based on an expansion in powers of 1/m 2 t can lead to poor high-energy behavior, an exact treatment of top-quark loops demonstrates that their effect is small and has limited phenomenological interest.
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ArXiv ePrint: 1610.02189
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Campbell, J.M., Keith Ellis, R. Top-quark loop corrections in Z+jet and Z + 2 jet production. J. High Energ. Phys. 2017, 20 (2017). https://doi.org/10.1007/JHEP01(2017)020
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DOI: https://doi.org/10.1007/JHEP01(2017)020