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arXiv · 1209.2938

Hyperelliptic curves of genus 3 with prescribed automorphism group

J. Gutierrez·D. Sevilla·T. Shaska
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Abstract

We study genus 3 hyperelliptic curves which have an extra involution. The locus $\L_3$ of these curves is a 3-dimensional subvariety in the genus 3 hyperelliptic moduli $\H_3$. We find a birational parametrization of this locus by affine 3-space. For every moduli point $\p \in \H_3$ such that $|\Aut (\p)|>2$, the field of moduli is a field of definition. We provide a rational model of the curve over its field of moduli for all moduli points $\p \in \H_3$ such that $|\Aut(\p)|>4$. This is the first time that such a rational model of these curves appears in the literature.

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J. Gutierrez, D. Sevilla, T. Shaska. 2012-09-13. Hyperelliptic curves of genus 3 with prescribed automorphism group. https://arxiv.org/abs/1209.2938

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