279 research outputs found
A Revisit of SO(6) Dynamical Symmetry in Nuclear Structure
According to the analysis based on the fermion dynamical symmetry model,
nuclei previously regarded as SO(6)-like (e.g. Xe and Pt) are
shown to be more akin to the transitional nuclei between SO(7) and SO(6)
symmetries
Spectroscopy of Po
Prompt, in-beam rays following the reaction Yb + 142 MeV
Si were measured at the ATLAS facility using 10 Compton-suppressed Ge
detectors and the Fragment Mass Analyzer. Transitions in Po were
identified and placed using -ray singles and coincidence data gated on
the mass of the evaporation residues. A level spectrum up to
J10 was established. The structure of Po is more
collective than that observed in the heavier polonium isotopes and indicates
that the structure has started to evolve towards the more collective nature
expected for deformed nuclei.Comment: 8 pages, revtex 3.0, 4 figs. available upon reques
An Introduction to Nuclear Supersymmetry: a Unification Scheme for Nuclei
The main ideas behind nuclear supersymmetry are presented, starting from the
basic concepts of symmetry and the methods of group theory in physics. We
propose new, more stringent experimental tests that probe the supersymmetry
classification in nuclei and point out that specific correlations should exist
for particle transfer intensities among supersymmetric partners. We also
discuss possible ways to generalize these ideas to cases where no dynamical
symmetries are present. The combination of these theoretical and experimental
studies may play a unifying role in nuclear phenomena.Comment: 40 pages, 11 figures, lecture notes `VIII Hispalensis International
Summer School: Exotic Nuclear Physics', Oromana, Sevilla, Spain, June 9-21,
200
Spin-rotor Interpretation of Identical Bands and Quantized Alignment in Superdeformed A 190 Nuclei
The ``identical'' bands in superdeformed mercury, thallium, and lead nuclei
are interpreted as examples of orbital angular momentum rotors with the weak
spin-orbit coupling of pseudo- symmetries and supersymmetries.Comment: 15 pages, revtex 3.0, 7 figures available upon request from
[email protected]
Formal comparison of SUSY in the nuclear U(6/2) model and in quantum field theory
A nuclear physics example of the U(6/2) supersymmetry group is considered. It
is shown that this group contains a supersymmetric subgroup with a structure
similar to the SUSY model of the quantum field theory (QFT). A comparison of
two models help to clarify the relation between the supersymmetry schemes of
QFT and of nuclear physics. Using this similarity a relation between the
numbers of the bosonic and fermionic states similar to the fundamental relation
in QFT is obtained. For those supermultiplets with at least two fermions the
number of the bosonic and fermionic states are equal as in QFT.Comment: 11 pages and one eps-figure. Phys.Rev.C (1999) in pres
Mg(, )Na reaction study for spectroscopy of Na
The Mg(, )Na reaction was measured at the Holifield
Radioactive Ion Beam Facility at Oak Ridge National Laboratory in order to
better constrain spins and parities of energy levels in Na for the
astrophysically important F()Ne reaction rate
calculation. 31 MeV proton beams from the 25-MV tandem accelerator and enriched
Mg solid targets were used. Recoiling He particles from the
Mg(, )Na reaction were detected by a highly segmented
silicon detector array which measured the yields of He particles over a
range of angles simultaneously. A new level at 6661 5 keV was observed in
the present work. The extracted angular distributions for the first four levels
of Na and Distorted Wave Born Approximation (DWBA) calculations were
compared to verify and extract angular momentum transfer.Comment: 11 pages, 6 figures, proceedings of the 18th International Conference
on Accelerators and Beam Utilization (ICABU2014
Studies of the electric dipole transitions of deformed rare-earth nuclei
Spectrum and electric dipole transition rates and relative intensities in
Sm, Gd, Dy are studied in the framework of
the interacting boson model with s,p,d,f bosons. It is found that E1 transition
data among the low-lying levels are in good agreement with the SU(3) dynamical
symmetry of the spdf interacting boson model proposed by Engel and Iachello to
describe collective rotation with octupole vibration. These results show that
these nuclei have SU(3) dynamic symmetry to a good approximation. Also in this
work many algebraic expressions for electric dipole transitions in the SU(3)
limit of the spdf-IBM have been obtained. These formulae together with the
formulae given previously exhaust nearly all the E1 transitions for low-lying
negative parity states. They are useful in analyzing experimental data.Comment: 26 pages, 1 figur
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