N=4 SYM NMHV Loop Amplitude in Superspace

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 $A(\Lambda^{-}\Lambda^{-}\Lambda^{-}\Lambda^{+}\Lambda^{+}\Lambda^{+})$and all scalar $A(\phi\phi\phi\phi\phi\phi)$scattering amplitude. A discussion of using MHV vertex approach to obtain these amplitudes are given, which implies a simplification for general loop amplitudes.