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Magnetized (Shift-)Orientifolds

Gianfranco Pradisi
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Abstract

We study four dimensional $Z_2 \times Z_2$ (shift)-orientifolds in presence of internal magnetic fields and NS-NS $B$-field backgrounds, describing in some detail one explicit example with N=1 supersymmetry. These models are related by $T$-duality to orientifolds with $D$-branes intersecting at angles and exhibit, due to the background fields, a rank reduction of the gauge group and multiple matter families. Moreover, the low-energy spectra are chiral and anomaly free if $D5$-branes are present along the magnetized directions.

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Gianfranco Pradisi. 2003-10-15. Magnetized (Shift-)Orientifolds. https://arxiv.org/abs/hep-th/0210088

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