Transactions of the American Mathematical Society

Author(s): Tomasz Szemberg
Journal: Trans. Amer. Math. Soc. 353 (2001), 4963-4972.
MSC (2000): Primary 14J28; Secondary 14C20, 14E25
Posted: July 30, 2001
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We study linear systems on Enriques surfaces. We prove rationality of Seshadri constants of ample line bundles on Enriques surfaces and provide lower bounds on these numbers. We show the nonexistence of

-very ample line bundles on Enriques surfaces of degree

for $k\geq 1$ , thus answering an old question of Ballico and Sommese.

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Retrieve articles in Transactions of the American Mathematical Society with MSC (2000): 14J28, 14C20, 14E25

Tomasz Szemberg
Affiliation: Institute of Mathematics, Reymonta 4, PL-30-059 Kraków, Poland
Address at time of publication: Department of Mathematics, University of Essen, FB6 Mathematik, D-45117 Essen, Germany
Email: szemberg@im.uj.edu.pl

DOI: 10.1090/S0002-9947-01-02788-X
PII: S 0002-9947(01)02788-X
Keywords: Enriques surfaces, Seshadri constants, generation of jets, $k$-very ampleness
Received by editor(s): June 1, 2000
Posted: July 30, 2001
Additional Notes: Partially supported by KBN grant 2 P03A 00816
Copyright of article: Copyright 2001, American Mathematical Society

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