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arXiv · 0705.2366

Instantons and Holomorphic Couplings in Intersecting D-brane Models

Nikolas Akerblom·Ralph Blumenhagen·Dieter Lust·Maximilian Schmidt-Sommerfeld
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Abstract

We clarify certain aspects and discuss extensions of the recently introduced string D-instanton calculus (hep-th/0609191). The one-loop determinants are related to one-loop open string threshold corrections in intersecting D6-brane models. Utilising a non-renormalisation theorem for the holomorphic Wilsonian gauge kinetic functions, we derive a number of constraints for the moduli dependence of the matter field Kaehler potentials of intersecting D6-brane models on the torus. Moreover, we compute string one-loop corrections to the Fayet-Iliopoulos terms on the D6-branes finding that they are proportional to the gauge threshold corrections. Employing these results, we discuss the issue of holomorphy for E2-instanton corrections to the superpotential. Eventually, we discuss E2-instanton corrections to the gauge kinetic functions and the FI-terms.

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Nikolas Akerblom, Ralph Blumenhagen, Dieter Lust, Maximilian Schmidt-Sommerfeld. 2007-05-16. Instantons and Holomorphic Couplings in Intersecting D-brane Models. https://doi.org/10.1088/1126-6708%2F2007%2F08%2F044

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