학술논문
Laser spectroscopy of neutron-rich $^{207,208}$Hg isotopes: Illuminating the kink and odd-even staggering in charge radii across the $N=126$ shell closure
Document Type
Working Paper
Author
Goodacre, T. Day; Afanasjev, A. V.; Barzakh, A. E.; Marsh, B. A.; Sels, S.; Ring, P.; Nakada, H.; Andreyev, A. N.; Van Duppen, P.; Althubiti, N. A.; Andel, B.; Atanasov, D.; Billowes, J.; Blaum, K.; Cocolios, T. E.; Cubiss, J. G.; Farooq-Smith, G. J.; Fedorov, D. V.; Fedosseev, V. N.; Flanagan, K. T.; Ganey, L. P.; Ghys, L.; Huyse, M.; Kreim, S.; Lunney, D.; Lynch, K. M.; Manea, V.; Palenzuela, Y. Martinez; Molkanov, P. L.; Rosenbusch, M.; Rossel, R. E.; Rothe, S.; Schweikhard, L.; Seliverstov, M. D.; Spagnoletti, P.; Van Beveren, C.; Veinhard, M.; Verstraelen, E.; Welker, A.; Wendt, K.; Wienholtz, F.; Wolf, R. N.; Zadvornaya, A.; Zuber, K.
Source
Physical Review Letters 126, 032502 (2021)
Subject
Language
Abstract
The mean-square charge radii of $^{207,208}$Hg ($Z=80, N=127,128$) have been studied for the first time and those of $^{202,203,206}$Hg ($N=122,123,126$) remeasured by the application of in-source resonance-ionization laser spectroscopy at ISOLDE (CERN). The characteristic \textit{kink} in the charge radii at the $N=126$ neutron shell closure has been revealed, providing the first information on its behavior below the $Z=82$ proton shell closure. A theoretical analysis has been performed within relativistic Hartree-Bogoliubov and non-relativistic Hartree-Fock-Bogoliubov approaches, considering both the new mercury results and existing lead data. Contrary to previous interpretations, it is demonstrated that both the kink at $N=126$ and the odd-even staggering (OES) in its vicinity can be described predominately at the mean-field level, and that pairing does not need to play a crucial role in their origin. A new OES mechanism is suggested, related to the staggering in the occupation of the different neutron orbitals in odd- and even-$A$ nuclei, facilitated by particle-vibration coupling for odd-$A$ nuclei.
Comment: 7 pages, 5 figures, Physical Review C, in press
Comment: 7 pages, 5 figures, Physical Review C, in press