%0 Journal Article %T Modularity in orbifold theory for vertex operator superalgebras %A Chongying Dong %A Zhongping Zhao %J Mathematics %D 2004 %I arXiv %R 10.1007/s00220-005-1418-2 %X This paper is about the orbifold theory for vertex operator superalgebras. Given a vertex operator superalgebra V and a finite automorphism group G of V, we show that the trace functions associated to the twisted sectors are holomorphic in the upper half plane for any commuting pairs in G under the C_2-cofinite condition. We also establish that these functions afford a representation of the full modular group if V is C_2-cofinite and g-rational for any g in G. %U http://arxiv.org/abs/math/0411524v1