  We considered the structure of steady-state plane-parallel radiative shock
waves propagating through the partially ionized hydrogen gas of temperature T_1
= 3000K and density 1e-12 gm/cm^3 <= \rho_1 <= 1e-9 gm/cm^3. The upstream Mach
numbers range within 6 <= M_1 <= 14. In frequency intervals of hydrogen lines
the radiation field was treated using the transfer equation in the frame of the
observer for the moving medium, whereas the continuum radiation was calculated
for the static medium. Doppler shifts in Balmer emission lines of the radiation
flux emerging from the upstream boundary of the shock wave model were found to
be roughly one-third of the shock wave velocity. The gas emitting the Balmer
line radiation is located at the rear of the shock wave in the hydrogen
recombination zone where the gas flow velocity in the frame of the observer is
approximately one-half of the shock wave velocity. The ratio of the Doppler
shift to the gas flow velocity of 0.7 results both from the small optical
thickness of the shock wave in line frequencies and the anisotropy of the
radiation field typical for the slab geometry. In the ambient gas with density
of \rho_1 >= 1e-11 gm/cm^3 the flux in the H-alpha frequency interval reveals
the double structure of the profile. A weaker H-beta profile doubling was found
for \rho_1 >= 1e-10 gm/cm^3 and U_1 <= 50 km/s. The unshifted redward component
of the double profile is due to photodeexcitation accompanying the rapid growth
of collisional ionization in the narrow layer in front of the discontinuous
jump.
