Nuclear charge radius of 9 Be from muonic atom spectroscopy using a microcalorimeter
The $2p\to1s$ transition energy in muonic $^9$Be was measured using a metallic magnetic calorimeter, resulting in $E_{2p\to 1s}=33\,391.48(34)\,$eV. The result is 30 times more precise than the previous best measurement and enables the extraction of the corresponding nuclear charge radius $r_c($$^9$Be$)=2.5506(51)\,$fm. It is $2.4$ times more precise than the commonly used value based on electron scattering and differs from it by $2.3$ times the combined uncertainties. This measurement represents the first determination of a nuclear charge radius using muonic x-ray spectroscopy with microcalorimeters.
Authors
- A. Fleischmann (ORCID: https://orcid.org/0000-0002-0218-5059)
- Noam Burger (ORCID: https://orcid.org/0009-0009-6347-5672)
- Michael Roosa (ORCID: https://orcid.org/0000-0002-3449-4665)
- W. G. Jiang (ORCID: https://orcid.org/0000-0001-8441-972X)
- Frederik Waûters (ORCID: https://orcid.org/0000-0001-9343-4251)
- Jorge Machado (ORCID: https://orcid.org/0000-0002-0383-4882)
- Stergiani Marina Vogiatzi (ORCID: https://orcid.org/0000-0002-4239-8673)
- Daniel Unger (ORCID: https://orcid.org/0009-0008-8204-9145)
- Daniel Hengstler (ORCID: https://orcid.org/0009-0001-0684-8067)
- K. Kirch (ORCID: https://orcid.org/0000-0002-1720-7636)
- A. Abeln
- Gonçalo Baptista (ORCID: https://orcid.org/0000-0002-0375-3433)
- L. Gastaldo (ORCID: https://orcid.org/0000-0002-7504-1849)
- T. E. Cocolios (ORCID: https://orcid.org/0000-0002-0456-7878)
- César Godinho (ORCID: https://orcid.org/0000-0003-3195-0394)
- Nitzan Goldberg (ORCID: https://orcid.org/0000-0002-9925-1779)
- Daniel Kreuzberger (ORCID: https://orcid.org/0009-0004-9291-4148)
- Nir Barnea (ORCID: https://orcid.org/0000-0001-8036-3052)
- Ulf-G. Meißner (ORCID: https://orcid.org/0000-0003-1254-442X)
- Randolf Pohl (ORCID: https://orcid.org/0000-0001-6435-659X)
- Ben Ohayon (ORCID: https://orcid.org/0000-0003-0045-5534)
- Michael Heines (ORCID: https://orcid.org/0000-0001-8723-5408)
- C. Enss (ORCID: https://orcid.org/0009-0004-2330-6982)
- Nancy Paul (ORCID: https://orcid.org/0000-0003-4469-780X)
- P. Indelicato (ORCID: https://orcid.org/0000-0003-4668-8958)
- Katharina von Schoeler (ORCID: https://orcid.org/0009-0005-2671-5869)
- Shikha Rathi (ORCID: https://orcid.org/0000-0002-0768-5546)
- Ofir Eizenberg (ORCID: https://orcid.org/0009-0000-0489-1582)
- Marie Deseyn (ORCID: https://orcid.org/0000-0002-1643-4079)
- Aziza Zendour
- Sonia Bacca (ORCID: https://orcid.org/0000-0002-9189-9458)
- Tim Egert (ORCID: https://orcid.org/0009-0007-3706-703X)
- Quentin Senetaire
- Andreas Knecht
- Johanna Walch
- Shihang Shen
- Tim Redelbach
Publication Details
- Journal
- Physical Review Letters
- Published
- 2026-11-06
- DOI
- https://doi.org/10.1103/l26q-678g
- Citations
- 3
- Primary Topic
- Nuclear physics research studies
- Type
- article
- Field-Weighted Citation Impact
- 2.55