We analyse soft supersymmetry breaking in type IIB de Sitter string vacua
after moduli stabilisation, focussing on models in which the Standard Model is
sequestered from the supersymmetry breaking sources and the spectrum of
soft-terms is hierarchically smaller than the gravitino mass m3/2. Due to
this feature, these models are compatible with gauge coupling unification and
TeV scale supersymmetry with no cosmological moduli problem. We determine the
influence on soft-terms of concrete realisations of de Sitter vacua constructed
from supersymmetric effective actions. One of these scenarios provides the
first study of soft-terms for consistent string models embedded in a compact
Calabi-Yau manifold with all moduli stabilised. Depending on the moduli
dependence of the Kaehler metric for matter fields and on the mechanism
responsible to obtain a de Sitter vacuum, we find two scenarios for
phenomenology: (i) a split-supersymmetry scenario where gaugino masses are
suppressed with respect to scalar masses: M1/2∼m3/2ϵ≪m0∼m3/2ϵ≪m3/2 for ϵ∼m3/2/MP≪1; (ii) a typical MSSM scenario where all soft-terms are of the same
order: M1/2∼m0∼m3/2ϵ≪m3/2. Background fluxes
determine the numerical coefficients of the soft-terms allowing for small
variations of parameters as is necessary to confront data and to interpolate
between different scenarios. We comment on different stringy origins of the
mu-term and potential sources of desequestering.Comment: 27 pages + appendices, 2 figure