title: Studies of pear-shaped nuclei using accelerated radioactive beams.
abstract: 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 amplified in such nuclei. Here we determine electric octupole transition strengths (a direct measure of octupole correlations) for short-lived isotopes of radon and radium. Coulomb excitation experiments were performed using accelerated beams of heavy, radioactive ions. Our data on (220)Rn and (224)Ra show clear evidence for stronger octupole deformation in the latter. The results enable discrimination between differing theoretical approaches to octupole correlations, and help to constrain suitable candidates for experimental studies of atomic electric-dipole moments that might reveal extensions to the standard model.
authors: Oliver Lodge Laboratory, University of Liverpool, Liverpool L69 7ZE, UK.
authors: L P
authors: LP
authors: Gaffney
authors: P A
authors: PA
authors: Butler
authors: M
authors: M
authors: Scheck
authors: A B
authors: AB
authors: Hayes
authors: F
authors: F
authors: Wenander
authors: M
authors: M
authors: Albers
authors: B
authors: B
authors: Bastin
authors: C
authors: C
authors: Bauer
authors: A
authors: A
authors: Blazhev
authors: S
authors: S
authors: Bönig
authors: N
authors: N
authors: Bree
authors: J
authors: J
authors: Cederkäll
authors: T
authors: T
authors: Chupp
authors: D
authors: D
authors: Cline
authors: T E
authors: TE
authors: Cocolios
authors: T
authors: T
authors: Davinson
authors: H
authors: H
authors: De Witte
authors: J
authors: J
authors: Diriken
authors: T
authors: T
authors: Grahn
authors: A
authors: A
authors: Herzan
authors: M
authors: M
authors: Huyse
authors: D G
authors: DG
authors: Jenkins
authors: D T
authors: DT
authors: Joss
authors: N
authors: N
authors: Kesteloot
authors: J
authors: J
authors: Konki
authors: M
authors: M
authors: Kowalczyk
authors: Th
authors: T
authors: Kröll
authors: E
authors: E
authors: Kwan
authors: R
authors: R
authors: Lutter
authors: K
authors: K
authors: Moschner
authors: P
authors: P
authors: Napiorkowski
authors: J
authors: J
authors: Pakarinen
authors: M
authors: M
authors: Pfeiffer
authors: D
authors: D
authors: Radeck
authors: P
authors: P
authors: Reiter
authors: K
authors: K
authors: Reynders
authors: S V
authors: SV
authors: Rigby
authors: L M
authors: LM
authors: Robledo
authors: M
authors: M
authors: Rudigier
authors: S
authors: S
authors: Sambi
authors: M
authors: M
authors: Seidlitz
authors: B
authors: B
authors: Siebeck
authors: T
authors: T
authors: Stora
authors: P
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authors: Thoele
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authors: P
authors: Van Duppen
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authors: MJ
authors: Vermeulen
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authors: von Schmid
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authors: Voulot
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authors: Warr
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authors: Wimmer
authors: K
authors: K
authors: Wrzosek-Lipska
authors: C Y
authors: CY
authors: Wu
authors: M
authors: M
authors: Zielinska
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