Continuous-wave generation of an anti-Stokes Raman laser on a number o
f blue-green argon-ion lines (4p-4s and 4p-3d) has been demonstrated w
ith optical pumping from metastable levels 3d'(2)G and 3d(4)F. It is f
ound that the population transfer rate is increased by a factor of 3-5
(and hence the output power of the Raman laser) owing to Coulomb diff
usion in the velocity space. The excitation and relaxation rates for t
he metastable level have been measured. The Bennett hole on the metast
able level has been recorded using the probe field technique. It has b
een shown that Coulomb diffusion changes the shape of the contour to a
n exponential cusplike profile. Its width exceeds the Lorentzian one b
y 100 times and is close to the Doppler width. Such a giant broadening
is also confirmed by the shape of the absorption saturation curve.