A class of Buekenhout unitals in the Hall plane

Abstract

Let U be the classical unital in PG(2, q2) secant to ℓ∞. By deriving PG(2, q2) with respect to a derivation set disjoint from U we obtain a new unital U′ in the Hall plane of order q2. We show that this unital contains O'Nan configurations and is not isomorphic to the known unitals of the Hall plane, hence it forms a new class of unitals in the Hall plane.