P-groups and automorphisms

G, 〖Z_p〗^2 and Z_p are the semi-direct product group of the direct and semi-direct products of p-groups according to φ. Z(G)={g∈G:ag=ga each a∈G} is a normal subgroup of G, and G is called the center. If an θ automorphism of G provide the condition g^(-1) θ(g)∈Z(G) for each g∈L, we denote θ is the central automorphism of G and we denote it 〖Aut〗_Z (G). In this study, we tried to obtain a form of central automorphisms by obtaining the center for the semi direct and direct products where p=3, p=5 and θ is homomorphism from Z_p to automorphisms group of 〖Z_p〗^2.