8 citations · 28 across the 23 of their papers we have counts for
24 papers
The 2-divisibility of divisors on K3 surfaces in characteristic 2
Toshiyuki Katsura, Shigeyuki Kondō, Matthias Schütt
We show that K3 surfaces in characteristic 2 can admit sets of disjoint smooth rational curves whose sum is divisible by 2 in the Picard group, for each . More pr…
Normal forms for quasi-elliptic Enriques surfaces and applications
Toshiyuki Katsura, Matthias Schütt
We work out normal forms for quasi-elliptic Enriques surfaces and give several applications. These include torsors and numerically trivial automorphisms, but our main application i…
Kummer surfaces and quadratic line complexes in characteristic two
Toshiyuki Katsura, Shigeyuki Kondo
In this paper, we study the classical theory of quadratic line complexes and Kummer surfaces. A quadratic line complex is the intersection of the Grassmannian and a quadri…
Decomposed Richelot isogenies of Jacobian varieties of hyperelliptic curves and generalized Howe curves
Toshiyuki Katsura, Katsuyuki Takashima
We advance previous studies on decomposed Richelot isogenies (Katsura--Takashima (ANTS 2020) and Katsura (ArXiv 2021)) which are useful for analysing superspecial Richelot isogeny…
Coble surfaces in characteristic two
Toshiyuki Katsura, Shigeyuki Kondo
We study Coble surfaces in characteristic 2, in particular, singularities of their canonical coverings. As an application we classify Coble surfaces with finite automorphism group…
Decomposed Richelot isogenies of Jacobian varieties of curves of genus 3
Toshiyuki Katsura
For a nonsingular projective curve of genus 3 defined over an algebraically closed field of characteristic , we give a necessary and sufficient condition that the Jacobi…