Abstract
Abstract
We prove that every element of order 2 in the Brauer group of a complex Kummer surface X descends to an Enriques quotient of X. In generic cases, this gives a bijection between the set
${\mathcal Enr}(X)$
of Enriques quotients of X up to isomorphism and the set of Brauer classes of X of order 2. For some K3 surfaces of Picard rank
$20,$
we prove that the fibers of
${\mathcal Enr}(X)\to \mathrm {{Br}}(X)[2]$
above the nonzero points have the same cardinality.
Publisher
Cambridge University Press (CUP)
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