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Sigma-model anomalies in compact type IIB orientifolds and Fayet-Iliopoulos terms

L. E. Ibanez·R. Rabadan·A. M. Uranga
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Abstract

Compact Type IIB D=4, N=1 orientifolds have certain U(1) sigma model symmetries at the level of the effective Lagrangian. These symmetries are generically anomalous. We study the particular case of $Z_N$ orientifolds and find that these anomalies may be cancelled by a generalized Green-Schwarz mechanism. This mechanism works by the exchange of twisted RR-fields associated to the orbifold singularities and it requires the mixing between twisted and untwisted moduli of the orbifold. As a consequence, the Fayet-Iliopoulos terms which are present for the gauged anomalous U(1)'s of the models get an additional untwisted modulus dependent piece at the tree level.

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L. E. Ibanez, R. Rabadan, A. M. Uranga. 1999-05-13. Sigma-model anomalies in compact type IIB orientifolds and Fayet-Iliopoulos terms. https://doi.org/10.1016/s0550-3213(00)00059-6

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