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Dielectronic resonances of LMn and LNn (? 4) series in highly-charged M-shell tungsten ions



Dipti Goyal, A. Borovik, Jr., R. Silwal, Joan M. Dreiling, Amy C. Gall, Endre Takacs, Yuri Ralchenko


We present accurate spectroscopic measurements and detailed theoretical analysis of inner-shell LM$n$ and LN$n$ ($n$ $\geq$ 4) dielectronic resonances (DR) in highly-charged M-shell ions of tungsten. The x-ray emission from W$^49+}$ through W$^64+}$ was recorded at the electron beam ion trap (EBIT) facility at the National Institute of Standards and Technology (NIST) with a high-purity Ge detector for electron beam energies between 6.8 keV and 10.8 keV. The measured spectra clearly show the presence of strong resonance features as well as direct excitation spectral lines. The analysis of the recorded spectra with large-scale collisional-radiative (CR) modeling of the EBIT plasma allowed us to unambiguously identify numerous dielectronic resonances associated with excitations of the inner-shell $2s_1⁄2$, $2p_1⁄2$, and $2p_3/2}$ electrons. We also discuss different modeling strategies, importance of particular atomic processes for production of resonances, and future measurements with a new generation of microcalorimeters.
Physical Review A


Spectroscopy, Dielectronic resonances, Collisional-radiative modeling, M-shell ions.


Goyal, D. , Borovik, A. , Jr., R. , Silwal, J. , Dreiling, A. , Gall, E. and Takacs, Y. (2020), Dielectronic resonances of LMn and LNn (? 4) series in highly-charged M-shell tungsten ions, Physical Review A, [online],, (Accessed April 19, 2024)
Created March 4, 2020, Updated May 3, 2021