Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 2 of 2
Full-Text Articles in Physics
Nnlo Hard Functions In Massless Qcd, Alessandro Broggio, Andrea Ferroglia, Ben D. Pecjak, Zhibai Zhang
Nnlo Hard Functions In Massless Qcd, Alessandro Broggio, Andrea Ferroglia, Ben D. Pecjak, Zhibai Zhang
Publications and Research
We derive the hard functions for all 2 → 2 processes in massless QCD up to next-to-next-to-leading order (NNLO) in the strong coupling constant. By employing the known one- and two-loop helicity amplitudes for these processes, we obtain analytic expressions for the ultraviolet and infrared finite, minimally subtracted hard functions, which are matrices in color space. These hard functions will be useful in carrying out higher-order resummations in processes such as dijet and highly energetic top-quark pair production by means of soft-collinear effective theory methods.
Nnll Momentum-Space Resummation For Stop-Pair Production At The Lhc, Alessandro Broggio, Andrea Ferroglia, Matthias Neubert, Leonardo Vernazza, Li Lin Yang
Nnll Momentum-Space Resummation For Stop-Pair Production At The Lhc, Alessandro Broggio, Andrea Ferroglia, Matthias Neubert, Leonardo Vernazza, Li Lin Yang
Publications and Research
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 nextto- 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 …