Nets of conics containing a double line in $\mathrm{PG}(2,q)$, $q$ even
Nour Alnajjarine, Michel Lavrauw
Published: 2025/9/4
Abstract
In this paper, we complete the classification of nets of conics containing at least one double line in $\mathrm{PG}(2,q)$ for $q$ even. This classification is obtained by classifying the orbits of planes in $\mathrm{PG}(5,q)$ that intersect the nucleus plane in at least one point, under the action of the group that stabilizes the Veronese surface in $\mathrm{PG}(5,q)$ for $q\geq 4$ even. As a result, we show the existence of $18$ nets containing at least one double line, $9$ of which have an empty base.