Lifetime measurements and shape coexistence in {sup 144}Dy

Journal Article · Sat May 15 00:00:00 EDT 2010 · Physical Review. C, Nuclear Physics

DOI:https://doi.org/10.1103/PHYSREVC.81.054320· OSTI ID:21389028

Procter, M G; Cullen, D M; Niclasen, B; Mason, P J. R.; Rigby, S V; Dare, J A; Lumley, N M ^[1]; Scholey, C; Greenlees, P T; Jakobsson, U; Jones, P M; Julin, R; Juutinen, S; Ketelhut, S; Leino, M; Nyman, M; Puurunen, A; Rahkila, P; Ruotsalainen, P; Saren, J ^[2]

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1. Schuster Laboratory, University of Manchester, Manchester M13 9PL (United Kingdom)
2. Department of Physics, University of Jyvaeskylae, FIN-40014 Jyvaeskylae (Finland)

The known level scheme of {sup 144}Dy has been extended and lifetime measurements have been made with the recoil-distance Doppler-shift method. Reduced transition probabilities and deformations have been determined for four low-lying transitions. These states form part of the first observed band crossing, giving information on the change in nuclear deformation resulting from the rearrangement of h{sub 11/2} protons in the nucleus. Two bands built upon excited 10{sup +} states have been assigned pi(h{sub 11/2}){sup 2} prolate and nu(h{sub 11/2}){sup -2} oblate configurations with tau=12(2)ps and 0.01<tau < or approx. 16ns, respectively. These long lifetimes are reasoned to be a result of shape coexistence at low energy and moderate spin. A known four-quasiparticle dipole band has been extended to higher spin and lifetime measurements suggest a long-lived bandhead state. In this case, the excited states in the band may be consistent with a shears model interpretation of a magnetic dipole rotor. However, the measured B(M1)/B(E2) branching ratios reveal a larger than expected deformed rotational component compared with that in the analogous band in the lower mass isotone {sup 142}Gd.

• OSTI ID: 21389028
• Journal Information: Physical Review. C, Nuclear Physics, Vol. 81, Issue 5; Other Information: DOI: 10.1103/PhysRevC.81.054320; (c) 2010 The American Physical Society; ISSN 0556-2813
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
BRANCHING RATIO
CONFIGURATION
DOPPLER EFFECT
DYSPROSIUM 144
EXCITED STATES
GADOLINIUM 142
LIFETIME
MAGNETIC DIPOLES
MASS
NITROGEN 16
NUCLEAR DEFORMATION
PROTONS
RECOILS
SPIN
ANGULAR MOMENTUM
BARYONS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BETA-PLUS DECAY RADIOISOTOPES
DEFORMATION
DIMENSIONLESS NUMBERS
DIPOLES
DYSPROSIUM ISOTOPES
ELECTRON CAPTURE RADIOISOTOPES
ELEMENTARY PARTICLES
ENERGY LEVELS
EVEN-EVEN NUCLEI
FERMIONS
GADOLINIUM ISOTOPES
HADRONS
INTERMEDIATE MASS NUCLEI
ISOTOPES
LIGHT NUCLEI
MINUTES LIVING RADIOISOTOPES
MULTIPOLES
NITROGEN ISOTOPES
NUCLEI
NUCLEONS
ODD-ODD NUCLEI
PARTICLE PROPERTIES
RADIOISOTOPES
RARE EARTH NUCLEI
SECONDS LIVING RADIOISOTOPES