  We consider high-order correlation functions of the passive scalar in the
Kraichnan model. Using the instanton formalism we find the scaling exponents
$\zeta_n$ of the structure functions $S_n$ for $n\gg1$ under the additional
condition $d\zeta_2\gg1$ (where $d$ is the dimensionality of space). At $n<n_c$
(where $n_c = d\zeta_2/[2(2-\zeta_2)]$) the exponents are
$\zeta_n=(\zeta_2/4)(2n-n^2/n_c)$, while at $n>n_c$ they are $n$-independent:
$\zeta_n=\zeta_2 n_c/4$. We also estimate $n$-dependent factors in $S_n$,
particularly their behavior at $n$ close to $n_c$.

Chaotic Dynamics;Chaotic Dynamics