Laser Spectroscopy of Neutron-Rich 207,208Hg Isotopes: Illuminating the Kink and Odd-Even Staggering in Charge Radii across the N = 126 Shell Closure

Research output: Contribution to journalArticlepeer-review


  • Lars Ghys
  • A.V. Afanasjev
  • Thomas Day Goodacre
  • Anatoly (A.E.) Barzakh
  • Anatoly (A.E.) Barzakh
  • Bruce A Marsh
  • Simon Sels
  • P. Ring
  • Andrei N. Andreyev
  • Piet Van Duppen
  • Numa A. Althubiti
  • Boris Andel
  • Dimitar Atanasov

Institutes & Expert groups

  • KUL - Katholieke Universiteit Leuven
  • Mississippi State University
  • TUM - Technical University of Munich
  • CERN - Conseil Européen pour la Recherche Nucléaire
  • UNIMAN - The University of Manchester
  • PNPI - Petersburg Nuclear Physics Institute
  • University of York
  • ASRC - Advanced Science Research Center - JAEA
  • Comenius University Bratislava
  • IPP - Max-Planck-Institut für Plasmaphysik

Documents & links


The mean-square charge radii of 207;208Hg (Z ¼ 80, N ¼ 127, 128) have been studied for the first time and those of 202;203;206Hg (N ¼ 122, 123, 126) remeasured by the application of in-source resonance-ionization laser spectroscopy at ISOLDE (CERN). The characteristic 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 nonrelativistic 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 ¼ 126 and the odd-even staggering (OES) in its vicinity can be described predominately at the meanfield 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.


Original languageEnglish
Article number032502
Pages (from-to)1-7
Number of pages7
JournalPhysical review Letters
Issue number3
Publication statusPublished - 22 Jan 2021


  • Isotopes, Laser spectroscopy, Nuclear charge, Nuclear Phsyics

ID: 7087070