K3 x T^2/Z_2 orientifolds with fluxes, open string moduli and critical points

TL;DR

This paper extends the analysis of type IIB flux compactifications on K3×T^2/Z_2 to include D3 and D7 moduli, identifying supersymmetric Minkowski vacua and emphasizing the importance of symplectic section choices.

Contribution

It introduces a comprehensive supergravity framework incorporating D3 and D7 moduli in flux compactifications, revealing the structure of vacua and geometric considerations.

Findings

Identification of supersymmetric Minkowski vacua with fluxes

Analysis of the special geometry without symmetry assumptions

Highlighting the importance of symplectic section choices

Abstract

We extend the four-dimensional gauged supergravity analysis of type IIB vacua on $K3\times T^2/Z_2$ to the case where also D3 and D7 moduli, belonging to N=2 vector multiplets, are turned on. In this case, the overall special geometry does not correspond to a symmetric space, unless D3 or D7 moduli are switched off. In the presence of non--vanishing fluxes, we discuss supersymmetric critical points which correspond to Minkowski vacua, finding agreement with previous analysis. Finally, we point out that care is needed in the choice of the symplectic holomorphic sections of special geometry which enter the computation of the scalar potential.