Interspecies radiative transition in warm and superdense plasma mixtures

Area of Science:

• Plasma physics
• Atomic physics
• Astrophysical science

Background:

• Superdense plasmas are prevalent in planetary interiors and astrophysical objects.
• Atomic behavior in extreme-density conditions remains poorly understood, even for single-element plasmas.

Purpose of the Study:

• Investigate radiation spectra of superdense iron-zinc plasma mixtures.
• Explore atomic physics phenomena under extreme density and temperature conditions.

Main Methods:

• Applied thermal density functional theory.
• Performed ab initio calculations for plasma mixtures.
• Simulated conditions accessible by double-shell-target implosions (densities 250–2000 g cm⁻³, temperatures 50–100 eV).

Main Results:

• Revealed interspecies radiative transitions between different elements.
• Observed the breakdown of the dipole-selection rule for radiative transitions.
• Predicted that these phenomena can rival intra-atomic Kα-emission signals in superdense mixtures.

Conclusions:

• Atomic physics in superdense plasma mixtures exhibits novel phenomena.
• Interspecies and dipole-forbidden transitions are significant in extreme environments.
• These findings necessitate re-evaluation of radiation spectra models for dense plasmas.