Irreducible Heegner Divisors in the Period Space of Enriques Surfaces

Caner Koca; Ali Sinan Sertoz

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Irreducible Heegner Divisors in the Period Space of Enriques Surfaces

Caner Koca·Ali Sinan Sertoz

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Abstract

Reflection walls of certain primitive vectors in the anti-invariant sublattice of the K3 lattice define Heegner divisors in the period space of Enriques surfaces. We show that depending on the norm of these primitive vectors, these Heegner divisors are either irreducible or have two irreducible components. The two components are obtained as the walls orthogonal to primitive vectors of the same norm but of different type as ordinary or characteristic.

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BibTeX RIS

Caner Koca, Ali Sinan Sertoz. 2007-03-23. Irreducible Heegner Divisors in the Period Space of Enriques Surfaces. https://arxiv.org/abs/math/0509687

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