Buekenhout-Tits Unitals

Enumeration of Nonsingular Buekenhout Unitals

The only known enumeration of Buekenhout unitals occurs in the Desarguesian plane PG(2, q2). In this paper we develop general techniques for enumerating the nonsingular Buekenhout unitals embedded in any two-dimensional translation plane, and apply these techniques to obtain such an enumeration in the regular nearfield planes, the odd-order Hall planes, and the flag-transitive affine planes. We...

Enumeration of orthogonal Buekenhout unitals

In this paper we develop general techniques for enumerating orthogonal Buekenhout unitals embedded in two-dimensional translation planes. We then apply these techniques in the regular nearfield planes, the odd-order Hall planes, and the odd-order flag-transitive affine planes. Stabilizers of the resulting unitals also are computed.

Group theoretic characterizations of Buekenhout – Metz unitals in PG ( 2 , q 2 )

Let G be the group of projectivities stabilizing a unital U in PG(2, q2) and let A,B be two distinct points of U . In this paper we prove that, if G has an elation group of order q with center A and a group of projectivities stabilizing both A and B of order a divisor of q − 1 greater than 2(√q − 1), then U is an ovoidal Buekenhout–Metz unital. From this result two group theoretic characterizat...

Buekenhout unitals

Non-Existence of isomorphisms between certain unitals

We show that the Ree-Tits unitals are neither classical nor isomorphic to the polar unitals found in the Coulter-Matthews planes. To this end, we determine the full automorphism groups of the (finite) Ree unitals.