  The profile of a Bennett hole induced by laser field in ionic distribution in
collisional plasma is calculated. Influence of Chandrasekhar's dependence of
coefficients of velocity space transport on the profile is included into the
calculation for the first time. It is found that the hole narrows down as the
field detuning frequency increases. Physical cause of the effect is the falling
dependence of Coulomb collision frequency on the ionic velocity. Estimations
show that the effect is quite observable under conditions of high-current
gas-discharge plasma.
