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arXiv · hep-ph/9812397

Aspects of Type I String Phenomenology

L. E. Ibáñez·C. Muñoz·S. Rigolin
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Abstract

We study different phenomenological aspects of compact, D=4, N=1 Type IIB orientifolds considered as models for unification of the standard model and gravity. We discuss the structure of the compactification, string and unification scales depending on the different possible D-brane configurations. It is emphasized that in the context of Type I models the $M_W/M_{Planck}$ hierarchy problem is substantially alleviated and may be generated by geometrical factors. We obtain the effective low-energy supergravity Lagrangian and derive the form of soft SUSY-breaking terms under the assumption of dilaton/moduli dominance. We also discuss the role of anomalous U(1)'s and of twisted moduli in this class of theories. A novel mechanism based on the role of singularities is suggested to achieve consistency with gauge coupling unification in low string scale models.

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L. E. Ibáñez, C. Muñoz, S. Rigolin. 1999-02-09. Aspects of Type I String Phenomenology. https://doi.org/10.1016/s0550-3213(99)00264-3

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