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arXiv · 1511.03238

Gorenstein stable surfaces with $K_X^2 = 1$ and $p_g>0$

Marco Franciosi·Rita Pardini·Sönke Rollenske
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Abstract

In this paper we consider Gorenstein stable surfaces with $K^2_X=1$ and positive geometric genus. Extending classical results, we show that such surfaces admit a simple description as weighted complete intersection. We exhibit a wealth of surfaces of all possible Kodaira dimensions that occur as normalisations of Gorenstein stable surfaces with $K_X^2=1$; for $p_g=2$ this leads to a rough stratification of the moduli space. Explicit non-Gorenstein examples show that we need further techniques to understand all possible degenerations.

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Marco Franciosi, Rita Pardini, Sönke Rollenske. 2015-11-10. Gorenstein stable surfaces with $K_X^2 = 1$ and $p_g>0$. https://arxiv.org/abs/1511.03238

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