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arXiv · 1910.04772

Complete Form Factors in Yang-Mills from Unitarity and Spinor Helicity in Six Dimensions

Manuel Accettulli Huber·Andreas Brandhuber·Stefano De Angelis·Gabriele Travaglini
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Abstract

We present a systematic procedure to compute complete, analytic form factors of gauge-invariant operators at loop level in pure Yang-Mills. We consider applications to operators of the form $\mathrm{Tr}\, F^n$ where $F$ is the gluon field strength. Our approach is based on an extension to form factors of the dimensional reconstruction technique, in conjunction with the six-dimensional spinor-helicity formalism and generalised unitarity. For form factors this technique requires the introduction of additional scalar operators, for which we provide a systematic prescription. We also discuss a generalisation of dimensional reconstruction to any number of loops, both for amplitudes and form factors. Several novel results for one-loop minimal and non-minimal form factors of $\mathrm{Tr}\, F^n$ with $n>2$ are presented. Finally, we describe the \texttt{Mathematica} package \texttt{SpinorHelicity6D}, which is tailored to handle six-dimensional quantities written in the spinor-helicity formalism.

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Manuel Accettulli Huber, Andreas Brandhuber, Stefano De Angelis, Gabriele Travaglini. 2019-10-10. Complete Form Factors in Yang-Mills from Unitarity and Spinor Helicity in Six Dimensions. https://doi.org/10.1103/physrevd.101.026004

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