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arXiv · hep-ph/0508286

More about soft terms and FCNC in realistic string constructions

Tatsuo Kobayashi·Carlos Munoz
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Abstract

In realistic four-dimensional string constructions the presence of anomalous U(1)'s is generic. In addition, the associated Fayet-Iliopoulos contribution to the D-term can break the extra gauge symmetries. As a consequence, physical particles can appear combined with other states. We show that even if a three-generation standard-like model has originally flavour-independent soft scalar masses, the particle mixing contribution may generate non-universality among them. Thus FCNC effects which were apparently absent reappear. We also discuss the size of these contributions in an explicit model, and how they can be suppressed.

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Tatsuo Kobayashi, Carlos Munoz. 2005-10-17. More about soft terms and FCNC in realistic string constructions. https://doi.org/10.1088/1126-6708%2F2006%2F01%2F044

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