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Measurements of Strong-Interaction Effects in Kaonic-Helium Isotopes at sub-eV Precision with x-ray microcalorimeters



Tadashi Hashimoto, S Aikawa, T. Akaishi, M Bazzi, Douglas Bennett, M Berger, D Bosnar, A. D. Butt, C. Curceanu, W.Bertrand (Randy) Doriese, Malcolm Durkin, Y Ezoe, Joseph Fowler, H. Fujioka, Johnathon Gard, C Guaraldo, F.P. Gustafsson, C. Han, R Hayakawa, R. S. Hayano, T Hayashi, J. Hays-Wehle, Gene C. Hilton, T Hiraiwa, M Hiromoto, Y Ichinoge, M Iio, Y Iizawa, M Iliescu, S Ishimoto, Y Ishisaki, K Itahashi, M Iwasaki, Y Ma, T Murakami, T Nishi, H Noda, K Nomura, H Noumi, K Ooi, H Outa, K Piscicchia, Carl D. Reintsema, Y Sada, S Okada, Galen O'Neil, Dan Schmidt, Daniel Swetz, Joel Ullom, S Yamada, J Uhlig


We have measured the 3 d→ 2 p transition x rays of kaonic He 3 and He 4 atoms using superconducting transition-edge-sensor microcalorimeters with an energy resolution better than 6 eV (FWHM). We determined the energies to be 6224.5±0.4 (stat)±0.2 (syst) eV and 6463.7±0.3 (stat)±0.1 (syst) eV, and widths to be 2.5±1.0 (stat)±0.4 (syst) eV and 1.0±0.6 (stat)±0.3 (stat) eV, for kaonic He 3 and He 4, respectively. These values are nearly 10 times more precise than in previous measurements. Our results exclude the large strong-interaction shifts and widths that are suggested by a coupled-channel approach and agree with calculations based on optical-potential models.
Physical Review Letters


Kaonic Atoms, Strong-Interaction


Hashimoto, T. , Aikawa, S. , Akaishi, T. , Bazzi, M. , Bennett, D. , Berger, M. , Bosnar, D. , Butt, A. , Curceanu, C. , Doriese, W. , Durkin, M. , Ezoe, Y. , Fowler, J. , Fujioka, H. , Gard, J. , Guaraldo, C. , Gustafsson, F. , Han, C. , Hayakawa, R. , Hayano, R. , Hayashi, T. , Hays-Wehle, J. , Hilton, G. , Hiraiwa, T. , Hiromoto, M. , Ichinoge, Y. , Iio, M. , Iizawa, Y. , Iliescu, M. , Ishimoto, S. , Ishisaki, Y. , Itahashi, K. , Iwasaki, M. , Ma, Y. , Murakami, T. , Nishi, T. , Noda, H. , Nomura, K. , Noumi, H. , Ooi, K. , Outa, H. , Piscicchia, K. , Reintsema, C. , Sada, Y. , Okada, S. , O'Neil, G. , Schmidt, D. , Swetz, D. , Ullom, J. , Yamada, S. and Uhlig, J. (2022), Measurements of Strong-Interaction Effects in Kaonic-Helium Isotopes at sub-eV Precision with x-ray microcalorimeters, Physical Review Letters, [online],, (Accessed May 20, 2024)


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Created March 18, 2022, Updated May 3, 2023