Abstract
Let f: X → C be a “ general ” double covering of a smooth curve C of genus h ≥ 1. Here we show (with some restrictions on C if h ≥ 2) that there is no P ∈ X which is a common ramification point of all degree \({cal G} - 2h + 1\) morphisms X → P1.
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Ballico, E., Keem, C. Common Ramification Points of Pencils on Double Covering Curves. Results. Math. 46, 13–15 (2004). https://doi.org/10.1007/BF03322865
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DOI: https://doi.org/10.1007/BF03322865