Ricci curvature corrections to type II supergravity

Understand

We examine the NS-NS corrections to the type II supergravity given by Gross and Sloan, under the linear T-duality transformations.

• We show that the gravity and the B-field couplings are invariant under off-shell T-duality, whereas the dilaton couplings are invariant under on-shell T-duality.
• Requiring the compatibility of the dilaton couplings with off-shell T-duality as a guiding principle, we extend them to include the appropriate Ricci curvature and the divergence of the B-field strength.