The rank of the Cartier operator on Picard curves
Abstract
For an algebraic curve 𝒳 defined over an algebraically closed field of characteristic p>0, a-number a(𝒳) is the dimension of the space of exact holomorphic differentials on 𝒳. We computed the a-number for a family of certain Picard curves using the action of the Cartier operator on H0(𝒳,Ω1).
Communicated by Xiao-Dong Zhang