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On the perturbative corrections around D-string instantons

E. Gava·A. Hammou·J. F. Morales·K. S. Narain
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Abstract

We study ${\cal F}^4$-threshold corrections in an eight dimensional S-dual pair of string theories, as a prototype of dual string vacua with sixteen supercharges. We show that the orbifold CFT description of D-string instantons gives rise to a perturbative expansion similar to the one appearing on the fundamental string side. By an explicit calculation, using the Nambu-Goto action in the static gauge, we show that the first subleading term agrees precisely on the two sides. We then give a general argument to show that the agreement extends to all orders.

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E. Gava, A. Hammou, J. F. Morales, K. S. Narain. 1999-02-26. On the perturbative corrections around D-string instantons. https://doi.org/10.1088/1126-6708%2F1999%2F03%2F023

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