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Spectroscopic study of the 4 f 7 6 s 2 8 S 7/2∘−4 f 7 ( 8 S )6 s 6 p ( 1 P ) 8 P 9/2 transition in neutral europium-151 and europium-153: absolute frequency and hyperfine structure

We report on spectroscopic measurements on the$4f76s28S7/2∘<#comment/>→<#comment/>4f7(8S∘<#comment/>)6s6p(1P∘<#comment/>)8P9/2$transition in neutral europium-151 and europium-153 at 459.4 nm. The center of gravity frequencies for the 151 and 153 isotopes, reported for the first time in this paper, to our knowledge, were found to be 652,389,757.16(34) MHz and 652,386,593.2(5) MHz, respectively. The hyperfine coefficients for the$6s6p(1P∘<#comment/>)8P9/2$state were found to be$A(151)=−<#comment/>228.84(2)MHz$,$B(151)=226.9(5)MHz$and$A(153)=−<#comment/>101.87(6)MHz$,$B(153)=575.4(1.5)MHz$, which all agree with previously published results except for A(153), which shows a small discrepancy. The isotope shift is found to be 3163.8(6) MHz, which also has a discrepancy with previously published results.

Authors:
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Publication Date:
NSF-PAR ID:
10370777
Journal Name:
Journal of the Optical Society of America B
Volume:
39
Issue:
10
Page Range or eLocation-ID:
Article No. 2596
ISSN:
0740-3224; JOBPDE
Publisher:
Optical Society of America
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