NOTICE: Due to a lapse in annual appropriations, most of this website is not being updated. Learn more.
Form submissions will still be accepted but will not receive responses at this time. Sections of this site for programs using non-appropriated funds (such as NVLAP) or those that are excepted from the shutdown (such as CHIPS and NVD) will continue to be updated.
An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Determination of the isotopic change in nuclear charge radius from extreme-ultraviolet spectroscopy of highly charged ions of Xe
Published
Author(s)
Yuri Ralchenko, Roshani Silwal, A. Lapierre, John Gillaspy, Joan M. Dreiling, S A. Blundell, Dipti Goyal, A. Borovik, Jr., G Gwinner, A.C.C. Villari, Endre Takacs
Abstract
The electron beam ion trap (EBIT) at the National Institute of Standards and Technology was employed to measure the isotopic shift of the Na-like D 3s 2S1=2 3p 2P1=2;3=2, Mg-like 3s2 1S0 3s3p 1P1, Mg-like 3s2 1S0 3s3p 3P1, Al-like 3s23p 2P1=2 3s23p 2P3=2, and Al-like 3s23p 2P1=2 3s23d 2D3=2 transitions for the xenon isotopes, 124Xe and 136Xe. By combining the measured shift of the Na-like D1 and Mg-like 3s2 1S0 3s3p 3P1 transitions with highly accurate atomic-structure calculations, the difference in the mean-square nuclear charge radius of the two xenon isotopes was determined to be 0.269 fm2 0.042 fm2 and 0.268 fm2 0.045 fm2 respectively, yielding an average value of 0.269 fm2 0.031 fm2. The average result is twice more precise than the previous results obtained from x-ray spectroscopy of muonic atoms, laser spectroscopy of neutral xenon atoms, and a global evaluation of charge radii. The average result is slightly outside the uncertainty of a result obtained from a King plot analysis of comparable precision. This illustrates that extreme ultraviolet spectroscopy of highly charged ions is a precise method for measurements of changes in the charge radii of isotopes, and that this method can be used to benchmark the conventional methods.
Ralchenko, Y.
, Silwal, R.
, Lapierre, A.
, Gillaspy, J.
, Dreiling, J.
, Blundell, S.
, Goyal, D.
, Borovik, A.
, Jr., G.
, Gwinner, A.
and Villari, E.
(2020),
Determination of the isotopic change in nuclear charge radius from extreme-ultraviolet spectroscopy of highly charged ions of Xe, Physical Review A, [online], https://doi.org/10.1103/PhysRevA.101.062512, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=929788
(Accessed October 9, 2025)