On jordanian deformations of AdS5and supergravity

We consider various homogeneous Yang–Baxter deformations of the AdS 5 × S 5 superstring that can be obtained from the η -deformed superstring and related models by singular boosts. The jordanian deformations we obtain in this way behave similarly to the η -deformed model with regard to supergravity: T dualizing the classical sigma model it is possible to find corresponding solutions of supergravity, which, however, have dilatons that prevent T dualizing back. Hence the backgrounds of these jordanian deformations are not solutions of supergravity. Still, they do satisfy a set of recently found modified supergravity equations which implies that the corresponding sigma models are scale invariant. The abelian models that we obtain by singular boosts do directly correspond to solutions of supergravity. In addition to our main results we consider contraction limits of our main example, which do correspond to supergravity solutions.