Symplectic desingularization of moduli space of sheaves on a K3 surface
arXiv:math/0404453
Abstract
Let be a projective K3 surface with generic polarization $\cO_X(1)$ and let be the moduli space of semistable torsion-free sheaves on of rank 2, with Chern classes and . When is even, is a singular projective variety. We show that there is no symplectic desingularization of if is not an integer where is the Euler number of the Hilbert scheme of points in .