Contact Lie form and concircular geometry of locally conformally quasi-Sasakian manifolds

Abstract

We introduce a class of almost contact metric structures admitting a locally concircular transformation into a quasi-Sasakian structure, namely, locally concircularly quasi-Sasakian structures. We obtain a criterion that singles out this subclass of structures from the class of locally conformally quasi-Sasakian structures. Some applications and generalizations of this result are obtained.