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arXiv · hep-th/0110041

Dirichlet Branes on Orientifolds

N. Quiroz·B. Stefanski Jr
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Abstract

We consider the classification of BPS and non-BPS D-branes in orientifold models. In particular we construct all stable BPS and non-BPS D-branes in the Gimon-Polchinski (GP) and Dabholkar-Park-Blum-Zaffaroni (DPBZ) orientifolds and determine their stability regions in moduli space as well as decay products. We find several kinds of integrally and torsion charged non-BPS D-branes. Certain of these are found to have projective representations of the orientifold $\times$ GSO group on the Chan-Paton factors. It is found that the GP orientifold is not described by equivariant orthogonal K-theory as may have been at first expected. Instead a twisted version of this K-theory is expected to be relevant.

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N. Quiroz, B. Stefanski Jr. 2002-06-18. Dirichlet Branes on Orientifolds. https://doi.org/10.1103/physrevd.66.026002

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