  Let a given finite dimensional simple Lie superalgebra g possess an even
invariant non-degenerate supersymmetric bilinear form. We show how to recover
the quadratic Casimir element for the Kac-Moody superalgebra related to the
loop superalgebra with values in g from the quadratic Casimir element for g.
Our main tool here is an explicit Wick normal form of the even quadratic
Casimir operator for the Kac--Moody superalgebra associated with g; this Wick
normal form is of independent interest.
  If g possesses an odd invariant supersymmetric bilinear form we compute the
cubic Casimir element.
  In addition to the cases of Lie superalgebras g(A) with Cartan matrix A for
which the answer was known, we consider the Poisson Lie superalgebra poi(0|n)
and the related Kac--Moody superalgebra.
