Plasma diagnostics from intensities of resonance line series of He-like ions

Abstract

The possibility of using the relative intensities of the 1snp¹P₁–1s²¹S0 transitions with n = 3–6 in He-like multicharged ions to diagnose plasma in a nonstationary ionization state is considered. The calculations performed for F VIII ions show that, at electron temperatures of T_e = 10–100 eV, the intensity ratios are sensitive to the plasma electron density in the range of N_e = 10¹⁶–10²⁰ cm^–3. The universal calculated dependences can be used to diagnose various kinds of recombining or ionizing plasmas containing such ions.