  The space of local operators in the SU(2) invariant Thirring model (SU(2)
ITM) is studied by the form factor bootstrap method. By constructing sets of
form factors explicitly we define a susbspace of operators which has the same
character as the level one integrable highest weight representation of
\hat{sl_2}. This makes a correspondence between this subspace and the chiral
space of local operators in the underlying conformal field theory, the su(2)
Wess-Zumino-Witten model at level one.
