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Title: Energy Levels of Singly Ionized and Neutral Hafnium
Abstract

Improved energy levels for singly ionized and neutral hafnium of both even and odd parity are determined from Fourier transform spectrometer data using a least-squares optimization procedure. Data from interferometric spectrometers provide much tighter control of systematic uncertainties of line position measurements than can be achieved using dispersive spectrometers. The strong optical and near-UV lines connecting these levels are most likely to be used in the determination of isotopic abundance patterns. Comparisons of new results to published ones strongly suggest that our energy levels have systematic uncertainties in the mK (1 mK = 0.001 cm−1) range or smaller, and that widely used tables of energy levels for ionized Hf have systematic errors of approximately 70 mK.

Authors:
; ;
Award ID(s):
1814512
Publication Date:
NSF-PAR ID:
10361744
Journal Name:
The Astrophysical Journal Supplement Series
Volume:
258
Issue:
2
Page Range or eLocation-ID:
Article No. 27
ISSN:
0067-0049
Publisher:
DOI PREFIX: 10.3847
Sponsoring Org:
National Science Foundation
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