Collectivity in the light radon nuclei measured directly via Coulomb excitation

Gaffney, L. P.*; Robinson, A. P.*; Jenkins, D. G.*; Andreyev, A. N.; Bender, M.*; Blazhev, A.*; Bree, N.*; Bruyneel, B.*; Butler, P.*; Cocolios, T. E.*; Davinson, T.*; Daecon, A. N.*; De Witte, H.*; DiJulio, D.*; Diriken, J.*; Ekstrm, A.*; Fransen, Ch.*; Freeman, S. J.*; Geibel, K.*; Grahn, T.*; Hadinia, B.*; Hass, M.*; Heenen, P.-H.*; Hess, H.*; Huyse, M.*; Jakobsson, U.*; Kesteloot, N.*; Konki, J.*; Krll, T.*; Kumar, V.*; Ivanov, O.*; Martin-Haugh, S.*; Mcher, D.*; Orlandi, R.  ; Pakarinen, J.*; Petts, A.*; Peura, P.*; Rahkila, P.*; Reiter, P.*; Scheck, M.*; Seidlitz, M.*; Singh, K.*; Smith, J. F.*; Van De Walle, J.*; Van Duppen, P.*; Voulot, D.*; Wadsworth, R.*; Warr, N.*; Wenander, F.*; Wimmer, K.*; Wrzosek-Lipska, K.*; Zieliska, M.*

Radioactive ion beams of Rn were studied by means of low-energy Coulomb excitation at REX-ISOLDE, CERN. The electric-quadrupole (E2) matrix elements connecting the first excited 2 to the ground state of these nuclei was extracted, which permits to determine the collectivity of these isotopes, which in both cases is deduced to be weak, as expected from the low-lying level-energy scheme. Comparisons were also made with beyond-mean-field model calculations and the magnitude of the transitional quadrupole moments are well reproduced.