Holomorphic tachyons and fractional D-branes Original Research Article

We study tachyon condensation on brane–antibrane systems in orbifold theories from the viewpoint of boundary string field theory. We show that the condensation of holomorphic tachyon fields generates various fractional D-branes. The boundary N=2 supersymmetry in the worldsheet theory ensures this result exactly. Furthermore, our results are consistent with the twisted RR-charges from detailed calculations of boundary states. We also discuss the generation of RR-charges due to holomorphic tachyon fields on multiple brane–antibrane pairs in flat space.