We investigate the effect of an intense optical held on the energies o
f electrons ejected in an Auger process. To this end, part of a subpic
osecond, infrared laser beam is focused onto a metal target to produce
subpicosecond, broadband x radiation. Electrons resulting from the x-
ray-induced LMM Auger transition in argon are detected in a time-of-fl
ight electron spectrometer. The other part of the infrared laser beam
is directly focused onto the argon atoms. When the x-ray-induced Auger
transition takes piece in the presence of the intense dressing beam,
sidebands appear around the Auger peaks in the electron spectrum, corr
esponding to absorption or emission of photons from the dressing field
. The magnitude of the sidebands is studied as a function of dressing
field intensity. Good quantitative agreement with quantum-mechanical t
heory is reported.