D-branes at del Pezzo singularities: global embedding and moduli stabilisation

Abstract

In the context of type IIB string theory we combine moduli stabilisation and model building on branes at del Pezzo singularities in a fully consistent global compactification. By means of toric geometry, we classify all the Calabi-Yau manifolds with 3 < h 1,1 < 6 which admit two identical del Pezzo singularities mapped into each other under the orientifold involution. This effective singularity hosts the visible sector containing the Standard Model while the Kähler moduli are stabilised via a combination of D-terms, perturbative and non-perturbative effects supported on hidden sectors.We present concrete models where the visible sector, containing the Standard Model, gauge and matter content, is built via fractional D3-branes at del Pezzo singularities and all the Kähler moduli are fixed providing an explicit realisation of both KKLT and LARGE volume scenarios, the latter with D-term uplifting to de Sitter minima.We perform the consistency checks for global embedding such as tadpole, K-theory charges and Freed-Witten anomaly cancellation. We briefly discuss phenomenological and cosmological implications of our models.

Non-thermal CMSSM with a 125 GeV Higgs

“…In these models the contribution to gaugino masses from anomaly mediation turns out to be negligibly small and hence is distinct from other scenarios [17][18][19][20] where contributions from anomaly mediation are significant and where a Wino LSP can be realised. Apart from DM, these models are very promising since they can be embedded in globally consistent Calabi-Yau compactifications [47][48][49], allow for TeVscale SUSY and successful inflationary models [50][51][52], do not feature any cosmological moduli problem, 2 are compatible with gauge coupling unification and do not suffer from any moduli-induced gravitino problem [54,55]. Non-standard thermal history using CMSSM was considered in ref.…”

Analytic classes of metastable de Sitter vacua

“…In the simplest supergravity models that might arise in the presence of so-called non-geometric fluxes [6], numerical dS vacua where found in [7][8][9] and more recently in a more complicated model in [10]. Other interesting ways to construct de Sitter vacua using a single step mechanism in string theory motivated N = 1 supergravity models have been suggested over the years, for example in [11][12][13][14][15][16][17][18][19][20]. The single-step mechanism that stabilizes all moduli simultaneously in a de Sitter vacuum was also used in the recent papers [21,22].…”

De Sitter vacua from a D-term generated racetrack uplift

“…So a relatively mild suppression, for instance by warping, is required for this volume dependence. See also recent applications to explicit scenarios in [49,50] and also together with a string-loop correction in fibred Calabi-Yaus [51].…”

“…Even if there do not exist two divisors D 2 and D 3 that are rigid, one might still be able to effectively 'rigidify' one or more divisors by fixing all the deformation moduli of the corresponding D7-brane stacks via a gauge flux choice [49,55,56]. Under these assumptions, the superpotential in terms of the Kähler moduli T i = τ i + i ζ i is of the form…”

“…Such an explicit construction requires to match all known consistency conditions such as cancellation of Freed-Witten anomalies and cancellation of the D3, D5, and D7 tadpole [49,50,56,59,64]. We hope to report on an explicit example in another paper.…”