Abstract

The first results of a continuing analysis indicate that the ground configuration of the first ion of protactinium is 5f²7s², the ground level being ³H₄. 656 lines have been classified as combinations between 25 low–even and 164 high–odd energy levels; these represent approximately 35% of the lines that have been assigned to the second spectrum of protactinium. Four other low-lying levels have been assigned to the 5f²6d7s configuration. The importance of the use of hfs measurements in the level-searching program is stressed.

© 1967 Optical Society of America

First Spectrum of Protactinium*

A. Giacchetti
J. Opt. Soc. Am. 56(5) 653-657 (1966)

Term analysis of the spectrum of neutral neptunium (Np i)*

M. Fred, F. S. Tomkins, J. E. Blaise, P. Camus, and J. Vergès
J. Opt. Soc. Am. 67(1) 7-23 (1977)

Energy levels of the second spectrum of curium, Cm ii

Earl F. Worden, John G. Conway, and Jean Blaise
J. Opt. Soc. Am. B 3(8) 1092-1101 (1986)

Preliminary Level Analysis of the First and Second Spectra of Dysprosium, Dy i and Dy ii*

John G. Conway and Earl F. Worden
J. Opt. Soc. Am. 61(6) 704-726 (1971)

Level Structure of Singly Ionized Thulium (Tm ii)†

Nissan Spector
J. Opt. Soc. Am. 57(3) 312-317 (1967)