https://doi.org/10.1140/epjd/e2018-90118-7
Regular Article
Analysis of EUV spectra from N-shell tungsten ions observed with an electron beam ion trap
National Institute of Standards and Technology,
Gaithersburg,
MD
20899-8422, USA
d e-mail: yuri.ralchenko@nist.gov
Received:
14
March
2018
Received in final form:
11
May
2018
Published online: 3
July
2018
Extreme ultraviolet spectra of highly charged tungsten ions were produced with an electron beam ion trap at the National Institute of Standards and Technology and recorded with a flat-field grazing-incidence spectrometer. The spectra were measured in the wavelength range 2.7–17.3 nm while the beam energy varied between 1.65 and 2.00 keV. At these energies, the ionization stages from Zr-like W34+ to Se-like W40+ ions were observed. Large-scale collisional-radiative modelling was used to identify the strong lines, including 15 new ones, which represent electric dipole n = 4–4 transitions in these ions. While a good quantitative agreement between theoretical and experimental data was found for almost all ions, some of the tentatively identified wavelengths in W35+ significantly disagree from all available calculations.
Key words: Atomic Physics
© EDP Sciences / Società Italiana di Fisica / Springer-Verlag GmbH Germany, part of Springer Nature, 2018