Coulomb energy contribution to the excitation energy in ²²⁹Th and enhanced effect of variation

¹  School of Physics, The University of New South Wales - Sydney, NSW 2052, Australia
²  New Zealand Institute for Advanced Study, Massey University - Auckland, New Zealand
³  School of Physics and Astronomy, Tel Aviv University - Tel Aviv, 69978, Israel
⁴  Budker Institute of Nuclear Physics - 630090, Novosibirsk-90, Russia
⁵  Novosibirsk State University - 630090, Novosibirsk-90, Russia

Corresponding author: dmitriev@inp.nsk.su

Received: 13 October 2008
Accepted: 13 February 2009

Abstract

We estimated the polarization contribution of Coulomb energy to the spacing between the ground and first excited state of the ²²⁹Th nucleus as a function of the deformation parameter . We show that despite the fact that the odd particle is a neutron, the change in Coulomb energy between these two states can reach several hundreds keV from this contribution. This means that the effect of the variation of the fine-structure constant may be enhanced times in the E = 7.6 eV “nuclear clock” transition between the ground and first excited states in the ²²⁹Th nucleus. To extract the full value of , we propose to measure isomeric shift of atomic levels and nuclear electric quadrupole moments in ²²⁹Th.