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arXiv · hep-th/9906039

Gauge couplings in four-dimensional Type I string orbifolds

I. Antoniadis·C. Bachas·E. Dudas
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Abstract

We compute threshold effects to gauge couplings in four-dimensional $Z_N$ orientifold models of type I strings with ${\cal N}=2$ and ${\cal N}=1$ supersymmetry, and study their dependence on the geometric moduli. We also compute the tree-level (disk) couplings of the open sector gauge fields to the twisted closed string moduli of the orbifold in various models and study their effects and that of the one-loop threshold corrections on gauge coupling unification. We interpret the results from the (supergravity) effective theory point of view and comment on the conjectured heterotic-type I duality

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I. Antoniadis, C. Bachas, E. Dudas. 1999-09-16. Gauge couplings in four-dimensional Type I string orbifolds. https://doi.org/10.1016/s0550-3213(99)00452-6

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