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arXiv · 0909.0672

On surfaces with a canonical pencil

Roberto Pignatelli
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Abstract

We classify the minimal surfaces of general type with $K^2 \leq 4χ-8$ whose canonical map is composed with a pencil, up to a finite number of families. More precisely we prove that there is exactly one irreducible family for each value of $χ\gg 0$, $4χ-10 \leq K^2 \leq 4χ-8$. All these surfaces are complete intersections in a toric $4-$fold and bidouble covers of Hirzebruch surfaces. The surfaces with $K^2=4χ-8$ were previously constructed by Catanese as bidouble covers of $\PP^1 \times \PP^1$.

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Roberto Pignatelli. 2010-10-27. On surfaces with a canonical pencil. https://arxiv.org/abs/0909.0672

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