Limit theorems for probabilities of large deviations of a Galton-Watson process

We prove local and integral limit theorems for large deviations of Cramer type for a critical Galton–Watson branching process under the assumption that the radius of convergence of the generating function of the progeny is strictly greater than one. The proof is based on a modified Cramer approach which consists of construction of an auxiliary non-homogeneous in time branching process.
This research was supported by the Russian Foundation for Basic Research, grant 02–01–01252, and by INTAS, grants 99–01317, 00–265.