P fluxes and exotic branes

We consider the $$ mathcal{n} $$ = 1 superpotential generated in type-ii orientifold models by non-geometric fluxes. in particular, we focus on the family of p fluxes, that are related by t-duality transformations to the s-dual of the q flux. we determine the general rule that transforms a given flux in this family under a single t-duality transformation. this rule allows to derive a complete expression for the superpotential for both the iia and the iib theory for the particular case of a $$ {t}^6/left[{mathbb{z}}_2times {mathbb{z}}_2right] $$ orientifold. we then consider how these fluxes modify the generalised bianchi identities. in particular, we derive a fully consistent set of quadratic constraints coming from the ns-ns bianchi identities. on the other hand, the p flux bianchi identities induce tadpoles, and we determine a set of exotic branes that can be consistently included in order to cancel them. this is achieved by determining a universal transformation rule under t-duality satisfied by all the branes in string theory.