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arXiv · 0803.2513

(Non-)BPS bound states and D-brane instantons

Mirjam Cvetic·Robert Richter·Timo Weigand
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Abstract

We study non-perturbative effects in four-dimensional N=1 supersymmetric orientifold compactifications due to D-brane instantons which are generically not invariant under the orientifold projection. We show that they can yield superpotential contributions via a multi-instanton process at threshold. Some constituents of this configuration form bound states away from the wall of marginal stability which can decay in other regions of moduli space. A microscopic analysis reveals how contributions to the superpotential are possible when new BPS states compensate for their decay. We study this concretely for D2-brane instantons along decaying special Lagrangians in Type IIA and for D5-branes instantons carrying holomorphic bundles in Type I theory.

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Mirjam Cvetic, Robert Richter, Timo Weigand. 2008-06-30. (Non-)BPS bound states and D-brane instantons. https://doi.org/10.1088/1126-6708%2F2008%2F07%2F012

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