  We explain how to calculate the correlation function for SYM N=2 SO(3)-gauge
QFT with 4 flavors in terms of top Chern classes of the universal bundles over
the moduli spaces of rank 2 stable torsion free coherent sheaves with det=-1 on
the complex projective plane. We give a direct geometrical description of these
moduli spaces, study a 2-dimensional torus action on them, and calculate
several initial coefficients of the correlation function via Bott residue
formula.
