Soft Supersymmetry Breaking in KKLT Flux Compactification

TL;DR

The paper investigates soft supersymmetry breaking in KKLT flux compactifications with low-energy SUSY, where moduli are stabilized by fluxes and nonperturbative effects and a de Sitter vacuum is achieved via anti-D3 uplifting. It demonstrates that anomaly mediation is significant and, in realistic realizations, modulus mediation is of comparable size, yielding a distinctive sparticle spectrum with a mixed modulus-anomaly mediation pattern. The axion component of the modulus/dilaton superfield dynamically cancels the relative CP phase between anomaly and modulus contributions, addressing SUSY CP violation, while flavor is naturally controlled if matter resides on common brane sectors. The work analyzes one- and two-modulus models, deriving the SUSY-breaking order parameters, and discusses phenomenological implications, including preserved flavor/CP, cosmological considerations, and characteristic low-energy spectra.

Abstract

We examine the structure of soft supersymmetry breaking terms in KKLT models of flux compactification with low energy supersymmetry. Moduli are stabilized by fluxes and nonperturbative dynamics while a de Sitter vacuum is obtained by adding supersymmetry breaking anti-branes. We discuss the characteristic pattern of mass scales in such a set-up as well as some features of 4D N=1 supergravity breakdown by anti-branes. Anomaly mediation is found to always give an important contribution and one can easily arrange for flavor-independent soft terms. In its most attractive realization, the modulus mediation is comparable to the anomaly mediation, yielding a quite distinctive sparticle spectrum. In addition, the axion component of the modulus/dilaton superfield dynamically cancels the relative CP phase between the contributions of anomaly and modulus mediation, thereby avoiding dangerous SUSY CP violation.