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arXiv · 2608.19970

Explicit birational models of marked elliptic surfaces of relative degree two

Sönke Rollenske·Anna Ulivi·Aline Zanardini
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Abstract

We introduce explicit construction methods for two distinct birational models of elliptic surfaces equipped with a bisection --- or, more generally, a relative polarisation of degree two --- and double fibres. For Halphen surfaces of index two and Enriques surfaces, we illustrate how these give simple descriptions inside a toric variety.

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Sönke Rollenske, Anna Ulivi, Aline Zanardini. 2026-08-20. Explicit birational models of marked elliptic surfaces of relative degree two. https://arxiv.org/abs/2608.19970

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