Adopted values for the reduced electric quadrupole transition probability, B(E2)↑, from the ground state to the first-excited 2+ state of even–even nuclides are given in Table I. Values of τ, the mean life of the 2+ state; E, the energy; and β, the quadrupole deformation parameter, are also listed there. The ratio of β to the value expected from the single-particle model is presented. The intrinsic quadrupole moment, Q0, is deduced from the B(E2)↑ value. The product E×B(E2)↑ is expressed as a percentage of the energy-weighted total and isoscalar E2 sum-rule strengths.

Table II presents the data on which Table I is based, namely the experimental results for B(E2)↑ values with quoted uncertainties. Information is also given on the quantity measured and the method used. The literature has been covered to November 2000.

The adopted B(E2)↑ values are compared in Table III with the values given by systematics and by various theoretical models. Predictions of unmeasured B(E2)↑ values are also given in Table III.

Transition probability from the ground to the first-excited 2^+ state of even-even nuclides

Highly deformed intruder bands in the A≈130 mass region

Nuclear Data Sheets for A=132

Developing the Recoil Distance Doppler-Shift technique towards a versatile tool for lifetime measurements of excited nuclear states

We discuss the emergence of spatial structures in a ring laser model with transverse effects. The emphasis of this study is on the development of a description that can capture the essential features of transverse dynamics without the need for large-scale numerical efforts. We introduce an extension of the uniform field limit and derive a set of modal equations that we solve with conventional numerical methods. Our solutions show evidence of transverse mode competition in the laser dynamics, leading to both time-dependent and multimode stationary (cooperative frequency-locking) behaviors. In the time-dependent regime we analyze the resulting spatial structures and suggest a scheme for the investigation and characterization of spatial complexity.

Instabilities and spatial complexity in a laser

A rotational band has been studied in $^{132}\mathrm{Ce}$ to a spin above 50\ensuremath{\Elzxh}. Lifetime measurements have resulted in a large quadrupole moment corresponding to a deformation \ensuremath{\beta}\ensuremath{\sim}0.5. This is consistent with the moment of inertia determined from the energy-level spacing. These data are the first measurements of collectivity of discrete lines at high spin within the superdeformed second minimum.

Mean-lifetime measurements within the superdeformed second minimum in 132Ce.

Gamma-ray spectra of neutron-deficient isotopes between cerium ($Z=58$) and gadolinium ($Z=64$) have been investigated. New bands of states were identified in many even-even, odd-$A$, and odd-odd nuclei. This Letter reports results on the ground-state bands in the even-even nuclei $_{58}^{126}\mathrm{Ce}_{68}$, $_{60}^{128,\phantom{\rule{0ex}{0ex}}130,\phantom{\rule{0ex}{0ex}}132}\mathrm{Nd}_{68,\phantom{\rule{0ex}{0ex}}70,\phantom{\rule{0ex}{0ex}}72}$, $_{62}^{134,\phantom{\rule{0ex}{0ex}}136}\mathrm{Sm}_{72,\phantom{\rule{0ex}{0ex}}74}$, and $_{64}^{138,\phantom{\rule{0ex}{0ex}}140}\mathrm{Gd}_{74,\phantom{\rule{0ex}{0ex}}76}$. The systematic trends of deformation are presented and compared with theoretical predictions. The lightest isotopes appear to be axially symmetric rotors with ${\ensuremath{\epsilon}}_{2}\ensuremath{\gtrsim}0.3$.

Deformation of very light rare-earth nuclei.

Electromagnetic transition probabilities in 130Ce

A systematic study in the light rare earth (N 82, indicating that there is not a 'magic' superdeformed nucleus in the region. Striking population intensity differences are observed which are not explained by standard potential energy calculations. Open problems, particularly in connection with feeding into and out of the superdeformed bands, are discussed.

The new spectroscopy of superdeformed states: systematics in the light rare earths and unexpected feeding patterns

The lifetimes of 20 nuclear energy levels have been measured in 132,134Nd, 133,135Pm and 134,136Sm using the recoil distance technique. The nuclear reactions employed for studying these nuclei were 92Mo+46Ti and 92Mo+50Cr at beam energies of 210 MeV and 230 MeV respectively. The measured transition strengths in the yrast bands in 132,134Nd and 135Pm show a marked decrease over the expected rotational values, whilst the equivalent values in the 134,136Sm isotopes show very little decrease in collectivity. Nuclear deformations have been deduced for the low-lying states using axially symmetric rotational model assumptions. The results are compared with theoretical ground-state deformation predictions, and also with the results of the Grodzins' phenomenological formula which is based on the energy of the first 2+ state. The nuclear deformations are consistent with a transition to well deformed rotors as the number of neutrons decreases and also as the number of protons increases towards Z=64.

https://iopscience.iop.org/article/10.1088/0305-4616/13/2/009/pdf

P J Bishop

Papers

Mean-lifetime measurements within the superdeformed second minimum in 132Ce.

Deformation of very light rare-earth nuclei.

Electromagnetic transition probabilities in 130Ce

The new spectroscopy of superdeformed states: systematics in the light rare earths and unexpected feeding patterns

Lifetimes of low-lying levels in light rare earth nuclei around A=135