Magnetic field mixing and forbidden line emission in magnetized plasmas

Magnetic field mixing effects of atomic states and the resulting emission of forbidden lines from magnetized plasmas area potential diagnostic tool for magnetic field measurements in laboratory as well as astrophysical plasmas. To model this effect, we calculated magnetically induced line emission radiative decay rates with a physics model and code based on arelativistic multiconfiguration atomic structure theory. The results give the field dependent atomic states and transitionrates along with the characteristic mixing of states produced by the magnetic field. Further, these field-dependent atomic states can be used to calculate the line emission spectrum. The latter shows changes in the field free spectrum, including forbidden lines whose intensities are dependent on the magnetic field strength. We perform modelling calculations for L-shell n:3 - 2 line emission in neon-like silicon, argon and iron ions for magnetic fields in the mega-Gauss range forcomparison with experiments driven by the 1 MA Zebra pulse power generator. These results are also relevant for the interpretation of spectra from polars, like AM Herculis recorded by Chandra, where the estimated magnetic field can be up to hundreds of mega-Gauss.



This work is supported by DOE-NNSA grant DE-NA0003991, and by the Wootton Center for Astrophysical Plasma Properties under DOE cooperative agreement number DE-NA0003843.