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arXiv · hep-th/9711178

Classification of Flat Directions in Perturbative Heterotic Superstring Vacua with Anomalous U(1)

G. Cleaver·M. Cvetic·J. R. Espinosa·L. Everett·P. Langacker
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Abstract

We develop techniques to classify D- and F-flat directions for N=1 supersymmetric string vacua of the perturbative heterotic string theory, which possess an anomalous U(1) gauge group at the tree level. Genus-one corrections generate a Fayet-Iliopoulos term for the D-term of U(1)_A, which is canceled by non-zero vacuum expectation values (VEVs) of certain massless multiplets in such a way that the anomalous U(1) is broken, while maintaining the D- and F-flatness of the effective field theory. A systematic analysis of flat directions is given for non-zero VEVs of non-Abelian singlets, and the techniques are illustrated for a specific model. The approach sets the stage to classify the D- and F-flat directions for a large class of perturbative string vacua. This classification is a prerequisite to address systematically the phenomenological consequences of these models.

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G. Cleaver, M. Cvetic, J. R. Espinosa, L. Everett, P. Langacker. 1997-11-24. Classification of Flat Directions in Perturbative Heterotic Superstring Vacua with Anomalous U(1). https://doi.org/10.1016/s0550-3213(98)00277-6

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