Volume stabilization via α′ corrections in type IIB theory with fluxes

We consider the type IIB string theory in the presence of various extra 7/-brane pairs compactified on a warped Calabi-Yau threefold that admits a conifold singularity. We demonstrate that the volume modulus can be stabilized perturbatively at a non-supersymmetric AdS4/dS4 vacuum by the effective potential that includes the stringy (α')3 correction obtained by Becker et al. together with a combination of positive tension and anomalous negative tension terms generated by the additional 7-brane-antibrane pairs