M ar 2 00 7 On surfaces with p g = q = 1 and non - ruled bicanonical involution
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چکیده
This paper classifies surfaces of general type S with pg = q = 1 having an involution i such that S/i has non-negative Kodaira dimension and that the bicanonical map of S factors through the double cover induced by i. It is shown that S/i is regular and either: a) the Albanese fibration of S is of genus 2 or b) S has no genus 2 fibration and S/i is birational to a K3 surface. For case a) a list of possibilities and examples are given. An example for case b) with K2 = 6 is also constructed. 2000 Mathematics Classification: 14J29.
منابع مشابه
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تاریخ انتشار 2007