Fix a smooth very ample curve
C on a
K3 or abelian surface
X. Let
M \mathcal{M} denote the
moduli space of pairs of the form (
F,
s), where
F is a stable sheaf over
X whose Hilbert polynomial
coincides with that of the direct image, by the inclusion map of
C in
X, of a line bundle of degree
d
over
C, and
s is a nonzero section of
F. Assume
d to be sufficiently large such that
F has a nonzero
section. The pullback of the Mukai symplectic form on moduli spaces of stable sheaves over
X is
a holomorphic 2-form on
M \mathcal{M} . On the other hand,
M \mathcal{M} has a map to a Hilbert scheme parametrizing
0-dimensional subschemes of
X that sends (
F,
s) to the divisor, defined by
s, on the curve defined
by the support of
F. We prove that the above 2-form on
M \mathcal{M} coincides with the pullback of the
symplectic form on the Hilbert scheme.
Mathematics Subject Classification (2000): 53D30 - 14J60 - 14C05