DOCUMENTA MATHEMATICA, Vol. 17 (2012), 627-640

Florian Geiß

The Unirationality of Hurwitz Spaces of 6-Gonal Curves of Small Genus

In this short note we prove the unirationality of Hurwitz spaces of $6$-gonal curves of genus $g$ with $5 <= g <= 28$ or $g=30,31,35,36,40,45$. Key ingredient is a liaison construction in $\PP^1 \times \PP^2$. By semicontinuity, the proof of the dominance of this construction is reduced to a computation of a single curve over a finite field.

2010 Mathematics Subject Classification: 14H10, 14M20, 14M06, 14H51, 14Q05

Keywords and Phrases: Unirationality, Hurwitz space.

Full text: dvi.gz 26 k, dvi 73 k, ps.gz 276 k, pdf 169 k.