Searching for Dark Matter with the Th 229 Nuclear Lineshape from Laser Spectroscopy

authored by: Elina Fuchs, Fiona Kirk, Eric Madge, Chaitanya Paranjape, Ekkehard Peik, Gilad Perez, Wolfram Ratzinger, Johannes Tiedau
Abstract: The recent laser excitation of the low-lying Th229 isomer transition has started a revolution in ultralight dark matter searches. The enhanced sensitivity of this transition to the large class of dark matter models dominantly coupling to quarks and gluons will ultimately allow us to probe coupling strengths 8 orders of magnitude smaller than the current bounds from optical atomic clocks, which are mainly sensitive to dark matter couplings to electrons and photons. We argue that, with increasing precision, observations of the Th229 excitation spectrum will soon give the world-leading constraints. Using data from the pioneering laser excitation of Th229 by Tiedau et al. [Phys. Rev. Lett. 132, 182501 (2024)PRLTAO0031-900710.1103/PhysRevLett.132.182501], we present a first dark matter search in the excitation spectrum. While the exclusion limits of our detailed study of the lineshape are still below the sensitivity of currently operating clock experiments, we project the measurement of Zhang et al. [Nature (London) 633, 63 (2024)NATUAS0028-083610.1038/s41586-024-07839-6] to surpass it.
Organisation(s): Institute of Theoretical Physics
External Organisation(s): Physikalisch-Technische Bundesanstalt PTB
Weizmann Institute of Science
Universidad Autónoma de Madrid
Type: Article
Journal: Physical Review X
Volume: 15
No. of pages: 15
ISSN: 2160-3308
Publication date: 15.05.2025
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: General Physics and Astronomy
Electronic version(s): https://doi.org/10.1103/PhysRevX.15.021055 (Access: Open)
https://doi.org/10.48550/arXiv.2407.15924 (Access: Open)

BibTeX

@article{6ce94740ef37441bbfd60032be5a226a,
title = "Searching for Dark Matter with the Th 229 Nuclear Lineshape from Laser Spectroscopy",
abstract = "The recent laser excitation of the low-lying Th229 isomer transition has started a revolution in ultralight dark matter searches. The enhanced sensitivity of this transition to the large class of dark matter models dominantly coupling to quarks and gluons will ultimately allow us to probe coupling strengths 8 orders of magnitude smaller than the current bounds from optical atomic clocks, which are mainly sensitive to dark matter couplings to electrons and photons. We argue that, with increasing precision, observations of the Th229 excitation spectrum will soon give the world-leading constraints. Using data from the pioneering laser excitation of Th229 by Tiedau et al. [Phys. Rev. Lett. 132, 182501 (2024)PRLTAO0031-900710.1103/PhysRevLett.132.182501], we present a first dark matter search in the excitation spectrum. While the exclusion limits of our detailed study of the lineshape are still below the sensitivity of currently operating clock experiments, we project the measurement of Zhang et al. [Nature (London) 633, 63 (2024)NATUAS0028-083610.1038/s41586-024-07839-6] to surpass it.",
keywords = "hep-ph, nucl-ex, physics.atom-ph",
author = "Elina Fuchs and Fiona Kirk and Eric Madge and Chaitanya Paranjape and Ekkehard Peik and Gilad Perez and Wolfram Ratzinger and Johannes Tiedau",
note = "Publisher Copyright: {\textcopyright} 2025 authors.",
year = "2025",
month = may,
day = "15",
doi = "10.1103/PhysRevX.15.021055",
language = "English",
volume = "15",
journal = "Physical Review X",
issn = "2160-3308",
publisher = "American Physical Society",
number = "2",
}