Renormalization group flow in large Nc

We calculate renormalization group flow equations for the linear sigma-model in large N-c approximation. The flow equations decouple and can be solved analytically. The solution is equal to a self consistent solution of the NJL model in the same approximation, which shows that flow equations are a promising method to extend the calculation to higher order in 1/N-c. Including explicit chiral symmetry breaking, the large N-c approximation describes physics reasonably well. We further compare the analytic solution to the usually used polynomial truncation and find consistency. (C) 2002 Elsevier Science B.V. All rights reserved.