Spectra of W39+-W47+ in the 12 nm to 20 nm Region Observed With an EBIT Light Source

Published

October 14, 2007

Author(s)

Yuri Ralchenko, Joseph Reader, Joshua M. Pomeroy, Joseph N. Tan, John D. Gillaspy

Abstract

We observed spectra of highly ionized tungsten in the extreme ultraviolet with an electron beam ion trap (EBIT) and a grazing incidence spectrometer at the National Institute of Standards and Technology. Stages of ionization were distinguished by varying the energy of the electron beam between 2.1~keV and 4.3~keV and correlating the energies with spectral line emergence. The spectra were calibrated by separate spectra of highly ionized iron produced in the EBIT. Identification of the observed lines was aided by collisional-radiative modeling of the EBIT plasma. Good quantitative agreement was obtained between the modeling results and the experimental observations. Our line identifications complement recent results for W$^{40+}$-W$^{45+}$ observed in a tokamak plasma by P\{u}tterich {\it et al} (\jpb {\bf 38}, 3071, 2005). For most lines we agree with their assignment of ionization stage. Additionally, we present new identifications for some allowed and forbidden lines of W$^{39+}$, W$^{44+}$, W$^{46+}$, and W$^{47+}$. The uncertainties of our wavelengths range from 0.002 nm to 0.010 nm.

Citation

Journal of Physics B-Atomic Molecular and Optical Physics

Volume

40

Issue

19

Pub Type

Journals

Keywords

collisional-radiative modeling, EBIT, EUV spectra, highly-charged ions, tungsten

Citation

Ralchenko, Y. , Reader, J. , Pomeroy, J. , Tan, J. and Gillaspy, J. (2007), Spectra of W³⁹⁺-W⁴⁷⁺ in the 12 nm to 20 nm Region Observed With an EBIT Light Source, Journal of Physics B-Atomic Molecular and Optical Physics (Accessed April 18, 2024)