I am looking for an example of a smooth surface X with a fixed very ample mathcalOX(1) such that H1(mathcalO(k))=0 for all k
(such thing is called an ACM surface, I think) and a globally generated line bundle L such that L is torsion in Pic(X) and H1(L)neq0.
Does such surface exist? How can I construct one if it does exist? What if one ask for even nicer surface, such as arithmetically Gorenstein? If not, then I am willing to drop smooth or globally generated, but would like to keep the torsion condition.
More motivations(thanks Andrew): Such a line bundle would give a cyclic cover of X which is not ACM, which would be of interest to me. I suppose one can think of this as a special counter example to a weaker (CM) version of purity of branch locus.
To the best of my knowledge this is not a homework question (: But I do not know much geometry, so may be some one can tell me where to find an answer. Thanks.
EDIT: Removed the global generation condition, by Dmitri's answer. I realized I did not really need it that much.
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