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arXiv · hep-th/0507117

N=4 SYM NMHV Loop Amplitude in Superspace

Yu-tin Huang
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Abstract

Here we construct N=4 SuperYang-Mills 6 point NMHV loop amplitude (amplitudes with three minus helicities) as a full superspace form, using the $SU(4)_{R}$ anti-commuting spinor variables. Amplitudes with different external particle and cyclic helicity ordering are then just a particular expansion of this fermionic variable. We've verified this by explicit expansion obtaining amplitudes with two gluino calculated before. We give results for all gluino $A(Λ^{-}Λ^{-}Λ^{-}Λ^{+}Λ^{+}Λ^{+})$and all scalar $A(ϕϕϕϕϕϕ)$scattering amplitude. A discussion of using MHV vertex approach to obtain these amplitudes are given, which implies a simplification for general loop amplitudes.

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Yu-tin Huang. 2006-11-15. N=4 SYM NMHV Loop Amplitude in Superspace. https://doi.org/10.1016/j.physletb.2005.10.012

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