Euler obstruction, Brasselet number and critical points

Abstract

We relate the Brasselet number of a complex analytic functiongerm defined on a complex analytic set to the critical points of its real part on the regular locus of the link. Similarly we give a new characterization of the Euler obstruction in terms of the critical points on the regular part of the link of the projection on a generic real line. As a corollary, we obtain a new proof of the relation between the Euler obstruction and the Gauss-Bonnet measure, conjectured by Fu.