By combining a curved-crystal spectrometer, operated in Cauchois geometry, with a broad gamma-ray source with a continuous energy spectrum, it is possible to construct a tunable gamma-ray source from ...which monochromatic gamma-ray beams with small divergence and energies ranging from a few tens of keV up to a few MeV can be obtained.
.
The feasibility of measuring
g
-factors using the TDPAD method applied to high-energy, heavy fragmentation products is explored. The 2623keV
isomer in
192
Pb with
= 1.57 μs has been produced using ...the fragmentation of a 1
A
GeV
238
U beam. The results presented demonstrate for the first time that such heavy nuclei produced in a fragmentation reaction with a relativistic beam are sufficiently well spin-aligned. Moreover, the rather large value of the alignment, 28(10)% of the maximum possible, is preserved during the separation process allowing the determination of magnetic moments. The measured values of the lifetime,
= 1.54(9) μs, and the
g
-factor,
g
= - 0.175(20) , agree with the results of previous investigations using fusion-evaporation reactions.
Neutron-rich, radioactive Zn isotopes were investigated at the Radioactive Ion Beam facility REX-ISOLDE (CERN) using low-energy Coulomb excitation. The energy of the 2(1)+ state in 78Zn could be ...firmly established and for the first time the 2+ --> 0(1)+ transition in 80Zn was observed at 1492(1) keV. B(E2,2(1)+ --> 0(1)+) values were extracted for (74,76,78,80)Zn and compared to large scale shell model calculations. With only two protons outside the Z=28 proton core, 80Zn is the lightest N=50 isotone for which spectroscopic information has been obtained to date. Two sets of advanced shell model calculations reproduce the observed B(E2) systematics. The results for N=50 isotones indicate a good N=50 shell closure and a strong Z=28 proton core polarization. The new results serve as benchmarks to establish theoretical models, predicting the nuclear properties of the doubly magic nucleus 78Ni.
We examine a quantum phase transition in {gamma} -soft nuclei, where the O(6) limit is simultaneously a dynamical symmetry of the U(6) group of the interacting boson model and a critical point of a ...prolate-oblate phase transition. This is the only example of phase transitional behavior that can be described analytically for a finite s,d boson system.
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