Chiral logarithms in quenchedmπandfπ

Abstract
A diagrammatic analysis predicts that, in the quenched approximation, there should be no chiral logarithms, at leading order, in mπ or fπ, for gauge groups SU(N3). Morel has done an explicit calculation in the strong-gauge-coupling, large-dimension limit, and finds that there are such logarithms. I point out that Morel's calculation is of a quantity different from the quenched pion propagator. I show that if one calculates the correct quantity then there are no chiral logarithms. For SU(2), however, the diagrammatic analysis predicts that there are chiral logarithms in quenched mπ and fπ.