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arXiv · 1312.4703

Sphere-level Ramond-Ramond couplings in Ramond-Neveu-Schwarz formalism

Hamid R. Bakhtiarizadeh·Mohammad R. Garousi
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Abstract

We calculate in details the sphere-level scattering amplitude of two Ramond-Ramond (RR) and two Neveu-Schwarz-Neveu-Schwarz (NSNS) vertex operators in type II superstring theories in Ramond-Neveu-Schwarz (RNS) formalism. We then compare the expansion of this amplitude at order $α'^3$ with the eight-derivative couplings of the gravity and B-field that have been recently found based on S-dual and T-dual Ward identities. We find exact agreement. Moreover, using the above S-matrix element, we have found various couplings involving the dilaton field, and shown that they are also fully consistent with these Ward identities.

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Hamid R. Bakhtiarizadeh, Mohammad R. Garousi. 2014-05-08. Sphere-level Ramond-Ramond couplings in Ramond-Neveu-Schwarz formalism. https://doi.org/10.1016/j.nuclphysb.2014.05.002

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