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arXiv · hep-th/9605049

A D=4 N=1 Orbifold of Type I Strings

M. Berkooz·R. G. Leigh
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Abstract

We consider the propagation of Type I open superstrings on orbifolds with four non-compact dimensions and $N=1$ supersymmetry. In this paper, we concentrate on a non-trivial Z_2xZ_2 example. We show that consistency conditions, arising from tadpole cancellation and algebraic sources, require the existence of three sets of Dirichlet 5-branes. We discuss fully the enhancements of the spectrum when these 5-branes intersect. An amusing attribute of these models is the importance of the tree-level (in Type I language) superpotential to the consistent relationship between Higgsing and the motions of 5-branes.

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M. Berkooz, R. G. Leigh. 1996-05-07. A D=4 N=1 Orbifold of Type I Strings. https://doi.org/10.1016/s0550-3213(96)00543-3

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