Abstract
We present spectroscopic measurements and detailed theoretical analysis of inner-shell LMn and LNn(n ⩾ 4) dielectronic resonances in highly charged M -shell ions of tungsten. The x-ray emission from W49+ through W64+ was recorded at the electron-beam ion trap (EBIT) facility at the National Institute of Standards and Technology with a high-purity Ge detector for electron-beam energies between 6.8 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 modeling of the EBIT plasma allowed us to unambiguously identify numerous dielectronic resonances associated with excitations of the inner-shell 2s1/2 , 2p1/2 , and 2p3/2 electrons.