  We present a finite size spin wave calculation on the Heisenberg
antiferromagnet on the triangular lattice focusing in particular on the
low-energy part of the excitation spectrum. For s=1/2 the good agreement with
the exact diagonalization and quantum Monte Carlo results supports the
reliability of the spin wave expansion to describe the low-energy spin
excitations of the Heisenberg model even in presence of frustration. This
indicates that the spin susceptibility of the triangular antiferromagnet is
very close to the linear spin wave result.
