Second Spectrum of Tungsten (W II).

Area of Science:

• Atomic Physics
• Spectroscopy
• Computational Physics

Background:

• The tungsten W II spectrum analysis is crucial for understanding atomic properties.
• Previous studies in 1938 provided initial data on W II energy levels and spectral lines.

Purpose of the Study:

• To significantly expand the dataset for the W II spectrum.
• To classify a larger number of spectral lines and identify more energy levels.
• To investigate the coupling scheme of the W II ion.

Main Methods:

• Analysis of spectral lines within a specific wavelength range (1756.6 Å to 6219.77 Å).
• Classification of 2,173 W II lines.
• Determination of 62 even and 132 odd energy levels.

Main Results:

• An expanded catalog of 2,173 classified W II lines.
• Identification of 62 even and 132 odd energy levels, more than doubling previous findings.
• The ground state (6D0½) analysis indicates deviations from LS-coupling.

Conclusions:

• The W II spectrum is more comprehensively characterized with the new data.
• The observed level intervals and magnetic splitting factors suggest an intermediate coupling scheme (between LS and Jj) is more suitable for W II.