https://doi.org/10.1140/epja/s10050-024-01359-7
Regular Article - Experimental Physics
High-precision measurement of the atomic mass of 
and implications to isotope shift studies
1
Department of Physics, University of Jyväskylä, P.O. Box 35, FI-40014, Jyväskylä, Finland
2
School of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, 100871, Beijing, China
Received:
17
April
2024
Accepted:
14
June
2024
Published online:
15
July
2024
The absolute mass of was determined using the phase-imaging ion-cyclotron-resonance technique with the JYFLTRAP double Penning trap mass spectrometer. A more precise value for the mass of is essential for providing potential indications of physics beyond the Standard Model through high-precision isotope shift measurements of Sr atomic transition frequencies. The mass excess of was refined to be 
from high-precision cyclotron-frequency-ratio measurements with a relative precision of 
. The obtained mass-excess value is in agreement with the adopted value in the Atomic Mass Evaluation 2020, but is 30 times more precise. With this new value, we confirm the previously observed nonlinearity in the study of the isotope shift of strontium. Moreover, the double-beta (
) decay Q value of was directly determined to be 1790.115(37) keV, and the precision was improved by a factor of 30.
© The Author(s) 2024
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
