Stark broadening of the hydrogen Lyman-αline from the center to the near line wings for low-density plasmas

Hydrogen Lyman-α Stark broadening is calculated for a low-density plasma (N≤${10}^{14}$ ${\mathrm{cm}}^{\mathrm{-}3}$) for detunings smaller than 10 Å in the dipolar and no-quenching approximations. Semiclassical and quantal descriptions are alternatively used to describe the contribution of each collision. The results may be compared with the impact and static approximation limits, thus defining their range of validity and leading to analytical expressions for the relaxation rate in these cases. The effects of the trajectories curvatures and relative velocity variations are analyzed.