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We report on spectroscopic measurements on 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 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 6 s 6 p ( 1 P ∘ ) 8 P 9 / 2 state were found to be A ( 151 ) = − 228.84 ( 2 ) M H z , B ( 151 ) = 226.9 ( 5 ) M H z and A ( 153 ) = − 101.87 ( 6 ) M H z , B ( 153 ) = 575.4 ( 1.5 ) M H z , 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.
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Spectroscopic study of the 4f 7 6s 2 8 S 7/2∘ – 4f 7 ( 8 S ° ) 6s6p( 1 P ° ) 8 P 5/2,7/2 transitions in neutral europium-151 and europium-153: absolute frequency and hyperfine structure
We report on spectroscopic measurements on the 4f76s28S7/2∘−4f7(8S∘)6s6p(1P∘)8P5/2,7/2transitions at 466.32 nm and 462.85 nm, respectively, in neutral europium-151 and europium-153. The center of gravity frequencies for the 151 and 153 isotopes for both transitions are reported for the first time using saturated absorption spectroscopy. For the 6s6p(1P∘)8P5/2state, the center of gravity frequencies were found to be 642,894,493.3(4) MHz and 642,891,693.3(9) MHz for the 151 and 153 isotopes, respectively. The hyperfine constants for the upper state were found to beA(151)=−157.01(3)MHz,B(151)=74.5(4)MHz andA(153)=−69.43(14)MHz,B(153)=191.0(26)MHz. These hyperfine values are all consistent with previously published results except forB(151) that has a small discrepancy. The isotope shift was found to be 2799.54(20) MHz, a small discrepancy with previously published results. For the 6s6p(1P∘)8P7/2state, the center of gravity frequencies were found to be 647,708,930.6(6) MHz and 647,705,958.4(26) MHz for the 151 and 153 isotopes, respectively. The hyperfine constants for the upper state were found to beA(151)=−218.66(4)MHz,B(151)=−293.4(8)MHz andA(153)=−97.15(13)MHz,B(153)=−750(3)MHz. These values are all consistent with previously published results except forA(151) that has a small discrepancy. The isotope shift was found to be 2972.8(5) MHz, a small discrepancy with previously measured results.
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- Award ID(s):
- 2110311
- PAR ID:
- 10525070
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Journal of the Optical Society of America B
- Volume:
- 41
- Issue:
- 5
- ISSN:
- 0740-3224
- Page Range / eLocation ID:
- 1217
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1364/JOSAB.521181
