Quotients of schemes by ${\alpha }_p$ or ${\mu }_p$ actions in characteristic p>0

This paper studies schemes X defined over a field of characteristic p>0 which admit a nontrivial ${\alpha }_p$ or ${\mu }_p$ action. In particular, the structure of the quotient map $X\to Y$ is investigated. Information on local properties of the quotient Y, as singularities and local Picard groups, structure theorems for the quotient map and adjunction formulas for the quotient map are obtained.