Quelques "formules de masse" raffinées en degré premier

Abstract

For a local field with finite residue field of characteristique p, we give some refinements of Serre's mass formula in degree p which allow us to compute for example the contribution of cyclic extensions, or of those whose galoisian closure has a given group as group of automorphisms, or has ramification properties given in advance.

8 pages, corrected some typos