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arXiv · 2104.09234

Projective models of Nikulin orbifolds

Chiara Camere·Alice Garbagnati·Grzegorz Kapustka·Michał Kapustka
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Abstract

We study projective fourfolds of $K3^{[2]}$-type with a symplectic involution and the deformations of their quotients, called orbifolds of Nikulin types; they are IHS orbifolds. We compute the Riemann--Roch formula for Weil divisors on such orbifolds and describe the first complete family of orbifolds of Nikulin type with a polarization of degree $2$ as double covers of special complete intersections $(3,4)$ in $\mathbb{P}^6$.

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Chiara Camere, Alice Garbagnati, Grzegorz Kapustka, Michał Kapustka. 2021-04-19. Projective models of Nikulin orbifolds. https://doi.org/10.2140/ant.2024.18.165

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