Large shape staggering in neutron-deficient Bi isotopes

A. Barzakh (1) , A.  N. Andreyev (2, 3) , C. Raison (2) , J. G Cubiss (2) , P. van Duppen (4) , S. Péru (5) , S. Hilaire (5) , S. Goriely (6) , B. Andel (7) , S. Antalic (7) , M. Al Monthery (2) , J. C. Berengut (8) , J. Bieroń (9) , M. L. Bissell (10) , A. Borschevsky (11) , K. Chrysalidis (12, 13) , T. E. Cocolios (4) , T. Day Goodacre (10, 12, 14) , J.-P. Dognon (15) , M. Elantkowska (16) , E. Eliav (17) , G. J. Farooq-Smith (4) , D. V. Fedorov (1) , V. N. Fedosseev (12) , L. P. Gaffney (18) , R. F. Garcia Ruiz (10) , M. Godefroid (19) , C. Granados (4, 12) , R. D. Harding (2, 20) , R. Heinke (13) , M. Huyse (4) , J. Karls (12, 21) , P. Larmonier (12) , J. G. Li (22) , K. M. Lynch (12) , D.  E. Maison (1, 23) , B. A. Marsh (12) , P. Molkanov (1) , P. Mosat (7) , A. V. Oleynichenko (1, 24) , V. Panteleev (1) , P. Pyykkö (25) , M. L. Reitsma (11) , K. Rezynkina (4) , R.  E. Rossel (12) , S. Rothe (12) , J. Ruczkowski (16) , S. Schiffmann (19) , C. Seiffert (12) , M. D. Seliverstov (1) , S. Sels (4) , L.  V. Skripnikov (1, 24) , M. Stryjczyk (4, 26) , D. Studer (13) , M. Verlinde (4) , S. Wilman (16) , A.  V. Zaitsevskii (1, 24)

1 National Research Centre “Kurchatov Institute”: Petersburg Nuclear Physics Institute
2 Department of Physics, University of York, Heslington, York YO10 5DD, United Kingdom
3 Advanced Science Research Center and Nuclear Science Research Institute, Japan Atomic Energy Agency
4 K.U. LEUVEN - Instituut voor Kern- en Stralingsfysica
5 LMCE - Laboratoire Matière sous Conditions Extrêmes
6 IAA - Institut d'Astronomie et d'Astrophysique [Bruxelles]
7 Comenius University in Bratislava
8 School of Physics
9 Instytut Fizyki Teoretycznej
10 School of Physics and Astronomy [Manchester]
11 Van Swinderen Institute
12 CERN - European Organization for Nuclear Research
13 Institut für Physik Johannes Gutenberg Universität
14 TRIUMF [Vancouver]
15 LSDRM - Laboratoire Structure et Dynamique par Résonance Magnétique (LCF)
16 PUT - Poznan University of Technology
17 School of Chemistry
18 https://www.uwl.ac.uk/academic-schools/computing - School of Computing and Engineering [London]
19 SQUARES - Spectroscopy, Quantum Chemistry and Atmospheric Remote Sensing
20 CERC - CERC - Centre d'Études et de Recherches Comparatistes - EA 172
21 Department of Physics [Gothenburg]
22 IAPCM - Institute of Applied Physics and Computational Mathematics [Beijing]
23 SPBU - Saint Petersburg State University
24 Department of Chemistry, Lomonosov Moscow State University
25 Department of Chemistry [Helsinki]
26 JYU - University of Jyväskylä

The changes in the mean-square charge radius (relative to $^{209}$Bi), magnetic dipole, and electric quadrupole moments of $^{187;188;189;191}$Bi were measured using the in-source resonance-ionization spectroscopy technique at ISOLDE (CERN). A large staggering in radii was found in $^{187;188;189}$Bi$^g$ , manifested by a sharp radius increase for the ground state of $^{188}$Bi relative to the neighboring $^{187;189}$Bi$^g$. A large isomer shift was also observed for $^{188}$Bi$^m$. Both effects happen at the same neutron number, $N =$ 105, where the shape staggering and a similar isomer shift were observed in the mercury isotopes. Experimental results are reproduced by mean-field calculations where the ground or isomeric states were identified by the blocked quasiparticle configuration compatible with the observed spin, parity, and magnetic moment.

Domaines: Matériaux; Chimie théorique et/ou physique

A. Barzakh, A.  N. Andreyev, C. Raison, J. G Cubiss, P. van Duppen, et al.. Large shape staggering in neutron-deficient Bi isotopes. Physical Review Letters, 2021, 127 (19), pp.192501. ⟨10.1103/PhysRevLett.127.192501⟩. ⟨cea-03412363⟩