Studies of pear-shaped nuclei using accelerated radioactive beams

@article{Gaffney2013StudiesOP,
  title={Studies of pear-shaped nuclei using accelerated radioactive beams},
  author={L. P. Gaffney and P. A. Butler and M. Scheck and A. B. Hayes and Fredrik Wenander and M. L. Albers and B. Bastin and Christian Bauer and Andrey Blazhev and Stefan B{\"o}nig and Nick Bree and J. Cederk{\"a}ll and Timothy E. Chupp and Doug Cline and Thomas Elias Cocolios and T. Davinson and Hans De Witte and Jan Diriken and T. Grahn and A. Herz{\'a}ň and Marc Huyse and David G. Jenkins and David Joss and N. Kesteloot and J. Konki and M. Kowalczyk and Th. Kr{\"o}ll and Elaine Kwan and Rudolf Lutter and Kevin Moschner and P. J. Napiorkowski and Janne Pakarinen and Michael J. Pfeiffer and D{\'e}sir{\'e}e Radeck and P. Reiter and K. Reynders and Susan Rigby and Luis Miguel Robledo and M. Rudigier and Surinder Singh Sambi and Michael Seidlitz and Burkhard Siebeck and Thierry Stora and P. Thoele and Piet van Duppen and M.J. Vermeulen and Mirko von Schmid and Didier Voulot and Nigel Warr and K. Wimmer and Kasia Wrzosek-Lipska and C. Y. Wu and Magda Zielińska},
  journal={Nature},
  year={2013},
  volume={497},
  pages={199-204}
}
There is strong circumstantial evidence that certain heavy, unstable atomic nuclei are ‘octupole deformed’, that is, distorted into a pear shape. This contrasts with the more prevalent rugby-ball shape of nuclei with reflection-symmetric, quadrupole deformations. The elusive octupole deformed nuclei are of importance for nuclear structure theory, and also in searches for physics beyond the standard model; any measurable electric-dipole moment (a signature of the latter) is expected to be… 

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