One-loop soft theorems via dual superconformal symmetry

We study soft theorems at one loop in planar $$ mathcal{n}=4 $$ super yang-mills theory through finite order in the infrared regulator and to subleading order in the soft parameter δ. in particular, we derive a universal constraint from dual superconformal symmetry, which we use to bootstrap subleading log δ behaviour. moreover, we determine the complete infrared-finite subleading soft contribution of n-point mhv amplitudes using momentum twistors. finally, we compute the subleading log δ behaviour of one-loop nmhv ratio functions at six and seven points, finding that universality holds within but not between helicity sectors.