Abstract
First, we investigate SPG-reguli that satisfy one extra condition. Then we use a Buekenhout–Metz unital to construct a new SPG-regulus U in PG(5,q) that satisfies this property. Finally, we show that the semipartial geometry S (U) constructed from U is new and show that each automorphism of S(U) is induced by an element of PΓL (7,q) stabilising U.
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De Winter, S., Thas, J.A. SPG-Reguli Satisfying the Polar Property and a New Semipartial Geometry. Designs, Codes and Cryptography 32, 153–166 (2004). https://doi.org/10.1023/B:DESI.0000029219.90058.3a
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DOI: https://doi.org/10.1023/B:DESI.0000029219.90058.3a