European Physical Journal C: Particles and Fields (Aug 2021)
Identification of new isomers in $$^{228}$$ 228 Ac: impact on dark matter searches
- K. W. Kim,
- G. Adhikari,
- E. Barbosa de Souza,
- N. Carlin,
- J. J. Choi,
- S. Choi,
- M. Djamal,
- A. C. Ezeribe,
- L. E. França,
- C. Ha,
- I. S. Hahn,
- E. J. Jeon,
- J. H. Jo,
- W. G. Kang,
- M. Kauer,
- H. Kim,
- H. J. Kim,
- S. H. Kim,
- S. K. Kim,
- W. K. Kim,
- Y. D. Kim,
- Y. H. Kim,
- Y. J. Ko,
- E. K. Lee,
- H. Lee,
- H. S. Lee,
- H. Y. Lee,
- I. S. Lee,
- J. Lee,
- J. Y. Lee,
- M. H. Lee,
- S. H. Lee,
- S. M. Lee,
- D. S. Leonard,
- B. B. Manzato,
- R. H. Maruyama,
- R. J. Neal,
- S. L. Olsen,
- B. J. Park,
- H. K. Park,
- H. S. Park,
- K. S. Park,
- R. L. C. Pitta,
- H. Prihtiadi,
- S. J. Ra,
- C. Rott,
- K. A. Shin,
- A. Scarff,
- N. J. C. Spooner,
- W. G. Thompson,
- L. Yang,
- G. H. Yu,
- COSINE-100 Collaboration
Affiliations
- K. W. Kim
- Center for Underground Physics, Institute for Basic Science (IBS)
- G. Adhikari
- Department of Physics, University of California, San Diego
- E. Barbosa de Souza
- Department of Physics and Wright Laboratory, Yale University
- N. Carlin
- Physics Institute, University of São Paulo
- J. J. Choi
- Department of Physics and Astronomy, Seoul National University
- S. Choi
- Department of Physics and Astronomy, Seoul National University
- M. Djamal
- Department of Physics, Bandung Institute of Technology
- A. C. Ezeribe
- Department of Physics and Astronomy, University of Sheffield
- L. E. França
- Physics Institute, University of São Paulo
- C. Ha
- Department of Physics, Chung-Ang University
- I. S. Hahn
- Department of Science Education, Ewha Womans University
- E. J. Jeon
- Center for Underground Physics, Institute for Basic Science (IBS)
- J. H. Jo
- Department of Physics and Wright Laboratory, Yale University
- W. G. Kang
- Center for Underground Physics, Institute for Basic Science (IBS)
- M. Kauer
- Department of Physics and Wisconsin IceCube Particle Astrophysics Center, University of Wisconsin-Madison
- H. Kim
- Center for Underground Physics, Institute for Basic Science (IBS)
- H. J. Kim
- Department of Physics, Kyungpook National University
- S. H. Kim
- Center for Underground Physics, Institute for Basic Science (IBS)
- S. K. Kim
- Department of Physics and Astronomy, Seoul National University
- W. K. Kim
- Center for Underground Physics, Institute for Basic Science (IBS)
- Y. D. Kim
- Center for Underground Physics, Institute for Basic Science (IBS)
- Y. H. Kim
- Center for Underground Physics, Institute for Basic Science (IBS)
- Y. J. Ko
- Center for Underground Physics, Institute for Basic Science (IBS)
- E. K. Lee
- Center for Underground Physics, Institute for Basic Science (IBS)
- H. Lee
- Center for Underground Physics, Institute for Basic Science (IBS)
- H. S. Lee
- Center for Underground Physics, Institute for Basic Science (IBS)
- H. Y. Lee
- Center for Underground Physics, Institute for Basic Science (IBS)
- I. S. Lee
- Center for Underground Physics, Institute for Basic Science (IBS)
- J. Lee
- Center for Underground Physics, Institute for Basic Science (IBS)
- J. Y. Lee
- Department of Physics and Astronomy, Seoul National University
- M. H. Lee
- Center for Underground Physics, Institute for Basic Science (IBS)
- S. H. Lee
- Center for Underground Physics, Institute for Basic Science (IBS)
- S. M. Lee
- Department of Physics and Astronomy, Seoul National University
- D. S. Leonard
- Center for Underground Physics, Institute for Basic Science (IBS)
- B. B. Manzato
- Physics Institute, University of São Paulo
- R. H. Maruyama
- Department of Physics and Wright Laboratory, Yale University
- R. J. Neal
- Department of Physics and Astronomy, University of Sheffield
- S. L. Olsen
- Center for Underground Physics, Institute for Basic Science (IBS)
- B. J. Park
- Center for Underground Physics, Institute for Basic Science (IBS)
- H. K. Park
- Department of Accelerator Science, Korea University
- H. S. Park
- Korea Research Institute of Standards and Science
- K. S. Park
- Center for Underground Physics, Institute for Basic Science (IBS)
- R. L. C. Pitta
- Physics Institute, University of São Paulo
- H. Prihtiadi
- Center for Underground Physics, Institute for Basic Science (IBS)
- S. J. Ra
- Center for Underground Physics, Institute for Basic Science (IBS)
- C. Rott
- Department of Physics, Sungkyunkwan University
- K. A. Shin
- Center for Underground Physics, Institute for Basic Science (IBS)
- A. Scarff
- Department of Physics and Astronomy, University of Sheffield
- N. J. C. Spooner
- Department of Physics and Astronomy, University of Sheffield
- W. G. Thompson
- Department of Physics and Wright Laboratory, Yale University
- L. Yang
- Department of Physics, University of California, San Diego
- G. H. Yu
- Department of Physics, Sungkyunkwan University
- COSINE-100 Collaboration
- IBS School, University of Science and Technology (UST)
- DOI
- https://doi.org/10.1140/epjc/s10052-021-09473-2
- Journal volume & issue
-
Vol. 81,
no. 8
pp. 1 – 9
Abstract
Abstract We report the identification of metastable isomeric states of $$^{228}$$ 228 Ac at 6.28 keV, 6.67 keV and 20.19 keV, with lifetimes of an order of 100 ns. These states are produced by the $$\beta $$ β -decay of $$^{228}$$ 228 Ra, a component of the $$^{232}$$ 232 Th decay chain, with $$\beta $$ β Q-values of 39.52 keV, 39.13 keV and 25.61 keV, respectively. Due to the low Q-value of $$^{228}$$ 228 Ra as well as the relative abundance of $$^{232}$$ 232 Th and their progeny in low background experiments, these observations potentially impact the low-energy background modeling of dark matter search experiments.
