Let X be a smooth proper curve over a finite field of characteristic p. We
prove a product formula for p-adic epsilon factors of arithmetic D-modules on
X. In particular we deduce the analogous formula for overconvergent
F-isocrystals, which was conjectured previously. The p-adic product formula is
the equivalent in rigid cohomology of the Deligne-Laumon formula for epsilon
factors in l-adic \'etale cohomology (for a prime l different from p). One of
the main tools in the proof of this p-adic formula is a theorem of regular
stationary phase for arithmetic D-modules that we prove by microlocal
techniques.Comment: Revised version: some proofs and constructions detailed, notation
improved, index of notation added ; 88 page