2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/100151By extending the dressing symmetric action of IIB string in $AdS_5\times S^5$ to the $D_3$ brane, we find a gauged WZW action of Higgs Yang-Mills field including the 2-cocycle of axially anomaly. The left and right twistor structure of left and right $α$-planes glue into an ambitwistor. The symmetry group of Nahm equations is central extended to an affine group, thus we explain why the spectral curve is given by affine Toda.v2: strongly revised version (especially in important section 5), notation unified, typos corrected, referrences addedHigh Energy Physics - Theorytext