Nonlinear instantons from supersymmetric p-branes

Supersymmetric configurations of type II D-branes with nonzero gauge fieldstrengths in general supersymmetric backgrounds with nonzero B fields areanalyzed using the kappa-symmetric worldvolume action. It is found in dimensionfour or greater that the usual instanton equation for the gauge field obtains anonlinear deformation. The deformation is parameterized by the topological dataof the B-field, the background geometry and the cycle wrapped by the brane. Inthe appropriate dimensions, limits and settings these equations reduce todeformed instanton equations recently found in the context of noncommutativegeometry as well as those following from Lagrangians based on Bott-Chern forms.We further consider instantons comprised of M5-branes wrapping a Calabi-Yauspace with non-vanishing three-form field strengths. It is shown that theinstanton equations for the three-form are related to the Kodaira-Spencerequations.Comment: 35 pages, harvmac; small corrections in sections 3.3 and 3.5, references adde