On Surfaces with P G = 2, Q = 1 and Non-birational Bicanonical Map *
نویسندگان
چکیده
In the present note we show that any surface of general type over C with pg = 2,q = 1 and non birational bicanonical map has a pencil of curves of genus 2. Combining this result with previous ones, one obtains that an irregular surface S of general type with χ(S) ≥ 2 and non-birational bicanonical map has a pencil of curves of genus 2.
منابع مشابه
On Surfaces with P G = Q = 2 and Non-birational Bicanonical Map *
The present paper is devoted to the classification of irregular surfaces of general type with pg = q = 2 and non birational bicanonical map. The main result is that, if S is such a surface and if S is minimal with no pencil of curves of genus 2, then S is a double cover of a principally polarized abelian surface (A,Θ), with Θ irreducible. The double cover S → A is branched along a divisor B ∈ |...
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