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We report on a method for determining the absolute nuclear charge radius of high- elements using extreme-ultraviolet spectroscopy of highly charged Na-like ions in tandem with highly accurate atomic structure calculations of transition energy differences. The application of this method has reduced the nuclear charge radius uncertainty of by a factor of 8 from the currently accepted literature value, with a recently reported charge radius of 5.435(12) fm. The result reduces the charge radius uncertainty along the full Ir isotopic chain when combined with prior optical isotope shift measurements. The technique utilizes only a few million ions stored in an ion trap, which should apply to measurements with small quantities of radioactive nuclei. Published by the American Physical Society2025
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Absolute nuclear charge radius by Na-like spectral line separation in high-Z elements
Abstract We describe a novel technique to determine absolute nuclear radii of high-Znuclides. Utilizing accurate theoretical atomic structure calculations together with precise measurements of extreme ultraviolet transitions in highly charged ions this method allows for precise determinations of absolute nuclear charge radii based upon the well-known nuclear radii of their neighboring elements. This method can work for elements without stable isotopes, and its accuracy may be competitive with current methods (electron scattering and muonic x-ray spectroscopy).
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- PAR ID:
- 10540925
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- Journal of Physics B: Atomic, Molecular and Optical Physics
- Volume:
- 57
- Issue:
- 19
- ISSN:
- 0953-4075
- Format(s):
- Medium: X Size: Article No. 195001
- Size(s):
- Article No. 195001
- Sponsoring Org:
- National Science Foundation
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