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Irregular canonical double surfaces

Margarida Mendes Lopes·Rita Pardini
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Abstract

We study minimal surfaces X of general type with $K^2_X=6p_g-14$ and $q(X)>0$ such that $K_X$ is ample, the image of the canonical map is a canonically embedded surface of general type and the canonical map is not birational. The main result states that if X satisfies the above assumptions and $q(X)\ge 2$, then, apart from a finite number of exceptions, X belongs to an infinite series of examples due to Beauville. The exceptions are described in detail and some new examples are given.

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Margarida Mendes Lopes, Rita Pardini. 1997-02-27. Irregular canonical double surfaces. https://arxiv.org/abs/alg-geom/9611030

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