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arXiv · 2409.15996

Two-Loop Five-Point One-Mass Amplitudes in the Spinor-Helicity Formalism

Giuseppe De Laurentis
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Abstract

Processes involving electroweak vector bosons in association with jets are crucial for precision studies of the Standard Model at the Large Hadron Collider. Accurate predictions for the process $pp\rightarrow V(\rightarrow\bar\ell\ell)jj$ at next-to-next-to-leading order (NNLO), as well as N$^3$LO ones for the process with one fewer jet, require two-loop five-point one-mass amplitudes. These exhibit a significant increase in complexity compared to their massless counterparts. We present results for the partonic processes $\bar qQ\bar Qq\bar\ell\ell$ and $\bar qggq\bar\ell\ell$, with a forthcoming package for phenomenology. The present recalculation is based on the previous analytic results from ref. [1]. For the first time, we express two-loop five-point one-mass amplitudes in the spinor-helicity formalism. We achieve three orders of magnitude smaller expressions compared to previous results. This will facilitate phenomenological studies and help clarify mathematical properties of the amplitude.

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Giuseppe De Laurentis. 2024-09-24. Two-Loop Five-Point One-Mass Amplitudes in the Spinor-Helicity Formalism. https://arxiv.org/abs/2409.15996

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