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arXiv · 1312.4540

NNLL Momentum-Space Resummation for Stop-Pair Production at the LHC

Alessandro Broggio·Andrea Ferroglia·Matthias Neubert·Leonardo Vernazza·Li Lin Yang
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Abstract

If supersymmetry near the TeV scale is realized in Nature, the pair production of scalar top squarks is expected to be observable at the Large Hadron Collider. Recently, effective field-theory methods were employed to obtain approximate predictions for the cross section for this process, which include soft-gluon emission effects up to next-to-next-to-leading order (NNLO) in perturbation theory. In this work we employ the same techniques to resum soft-gluon emission effects to all orders in perturbation theory and with next-to-next-to-logarithmic (NNLL) accuracy. We analyze the effects of NNLL resummation on the stop-pair production cross section by obtaining NLO+NNLL predictions in pair invariant mass and one-particle inclusive kinematics. We compare the results of these calculations to the approximate NNLO predictions for the cross sections.

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Alessandro Broggio, Andrea Ferroglia, Matthias Neubert, Leonardo Vernazza, Li Lin Yang. 2013-12-16. NNLL Momentum-Space Resummation for Stop-Pair Production at the LHC. https://doi.org/10.1007/jhep03(2014)066

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