ar X iv : 0 90 1 . 03 69 v 3 [ m at h . A G ] 3 S ep 2 00 9 ON COX RINGS OF K 3 - SURFACES
نویسنده
چکیده
We study Cox rings of K3-surfaces. A first result is that a K3surface has a finitely generated Cox ring if and only if its effective cone is rational polyhedral. Moreover, we investigate degrees of generators and relations for Cox rings of K3-surfaces of Picard number two, and explicitly compute the Cox rings of generic K3-surfaces with a non-symplectic involution that have Picard number 2 to 5 or occur as double covers of del Pezzo surfaces.
منابع مشابه
ar X iv : h ep - p h / 03 12 27 6 v 1 1 9 D ec 2 00 3 The a 0 K + K − - vertex in light cone QCD sum rules
متن کامل
ar X iv : h ep - l at / 0 30 90 29 v 1 9 S ep 2 00 3 1 Progress in building an International Lattice Data Grid
We report on progress in setting up the International Lattice Data Grid. We describe the aims and objectives of the ILDG, what has been achieved during its first year of activity and invite feedback from the community.
متن کاملar X iv : h ep - t h / 03 12 24 4 v 1 1 9 D ec 2 00 3 FIAN / TD / 07 – 03 On Sp ( 2 M ) Invariant Green Functions
Explicit form of two-point and three-point Sp (2M) invariant Green functions is found.
متن کاملar X iv : m at h / 99 03 18 1 v 1 [ m at h . A G ] 3 0 M ar 1 99 9 PARABOLIC SHEAVES ON SURFACES AND AFFINE LIE ALGEBRA
متن کامل
ar X iv : h ep - e x / 04 03 02 0 v 1 1 2 M ar 2 00 4 Search for Θ + and Ξ − − 3 / 2 pentaquarks in HERA - B
A search for Θ + (1540) and Ξ −− 3/2 (1860) pentaquark candidates has been performed in proton-induced reactions on C, Ti and W targets at √ s = 41.6 GeV studying the pK 0 S resp. Ξ − π − and Ξ − π + (and charge conjugated (c.c.)) decay channels at mid-rapidity. With sensitivities of Br×dσ/dx F < 5 to 25 µb/nucleon, we find no evidence for narrow pentaquark peaks in any of the studied final sta...
متن کامل