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arXiv · 1311.2988

Holonomies of gauge fields in twistor space 6: incorporation of massive fermions

Yasuhiro Abe
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Abstract

Following the previous paper arXiv:1205.4827, we formulate an S-matrix functional for massive fermion ultra-helicity-violating (UHV) amplitudes, i.e., scattering amplitudes of positive-helicity gluons and a pair of massive fermions. The S-matrix functional realizes a massive extension of the Cachazo-Svrcek-Witten (CSW) rules in a functional language. Mass-dimension analysis implies that interactions among gluons and massive fermions should be decomposed into three-point massive fermion subamplitudes. Namely, such interactions are represented by combinations of three-point UHV and next-to-UHV (NUHV) vertices. This feature is qualitatively different from the massive scalar amplitudes where the number of involving gluons can be arbitrary.

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Yasuhiro Abe. 2014-01-24. Holonomies of gauge fields in twistor space 6: incorporation of massive fermions. https://doi.org/10.1016/j.nuclphysb.2014.01.012

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