Stark Broadening of Lyman-α in the Presence of a Strong Magnetic Field

Abstract

Stark broadening of Lyman-α of a hydrogen-like atom in the presence of a strong magnetic field is analyzed. The shape of the central (π) component of the Lorentz–Zeeman triplet is expressed analytically, taking into account the plasma coupling and microfield dynamic effects. It is shown that in a sufficiently strong magnetic field, the broadening of this component, contrary to the broadening of the lateral (σ) ones, is independent of the magnetic field and, therefore, can be used for the plasma density diagnostics. Comparison with computer simulations at conditions typical for tokamak divertors and white dwarf atmospheres shows a very good agreement.