Rational curves and Seshadri constants on Enriques surfaces

Galati, Concettina; Knutsen, Andreas

doi:10.1090/proc/16766

Rational curves and Seshadri constants on Enriques surfaces
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by Concettina Galati and Andreas Leopold Knutsen;

Proc. Amer. Math. Soc. 152 (2024), 3165-3175

DOI: https://doi.org/10.1090/proc/16766

Published electronically: June 12, 2024

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Abstract:

We prove that classes of rational curves on very general Enriques surfaces are always $2$-divisible. As a consequence, we compute the Seshadri constant of any big and nef line bundle on a very general Enriques surface, proving that it coincides with the value of the $\phi$-function introduced by Cossec [Math. Ann. 271 (1985), pp. 577–600].

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