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

An evaluation of A = 16{17 was published in Nuclear Physics A565 (1993), p. 1. This version of A = 16 diers from the published version in that we have corrected some errors discovered after the article went to press. It has also been slightly revised as of May 16 ,200 0t oinclud ehyperlink sfo rreference san dtables. Introductor ytables have been omitted from this manuscript. Also, Reference key numbers have been changed to the NNDC/TUNL format.

Energy Levels of Light Nuclei A =1 6

EPJ Web of Conferences

Adopted values for the excitation energy, &(3;), of the first 3- state of even-even nuclides are tabulated. Values of the reduced electric-octupole transition probability, B(E3;O: + 3;), from the ground state to this state, as determined from Coulomb excitation, lifetime measurements, inelastic electron scattering, deformation parameters /3s obtained from angular distributions of inelastically scattered nucleons and light ions, and other miscellaneous procedures are listed in separate tables. Adopted values for B(E3;O: + 3;) are presented in the final table, together with the E3 transition strengths, in Weisskopf units, and the product EA3;) X B(E3;O: --* 3;), expressed as a percentage of the energyweighted E3 sum-rule strength. An evaluation is made of the reliability of B(E3;O: + 31) values deduced from deformation parameters &. The literature has been covered to March 1988.

/pdf/for-even-even-nuclides-throughout-the-periodic-table-tacjid065q.pdf

For even-even nuclides throughout the periodic table

The compression-mode giant resonances and nuclear incompressibility

Despite a great success of the Skyrme mean-field approach in the exploration of nuclear dynamics, it seems to fail in the description of the spin-flip M1 giant resonance. The results for different Skyrme parameterizations are contradictory and poorly agree with experiment. In particular, there is no parameterization which simultaneously describes the one-peak gross structure of M1 strength in doubly magic nuclei and two-peak structure in heavy deformed nuclei. The reason of this mismatch could lie in an unsatisfactory treatment of spin correlations and spin–orbit interaction. We discuss the present status of the problem and possible ways of its solution. In particular, we inspect (i) the interplay of the collective shift and spin–orbit splitting, (ii) the isovector M1 response versus isospin-mixed responses and (iii) the role of tensor and isovector spin–orbit interaction.

/pdf/spin-flip-m1-giant-resonance-as-a-challenge-for-skyrme-76q49pph8l.pdf

Spin-flip M1 giant resonance as a challenge for Skyrme forces

Self-consistent factorization of two-body residual interaction is proposed for arbitrary densityand current-dependent energy functionals. Following this procedure, a separable RPA (SRPA) method is constructed. SRPA considerably simplifies the calculations and demonstrates quick convergence to exact results. The method is tested for SkI3 and SkM* forces.

Separable random phase approximation for self-consistent nuclear models

We formulate the self-consistent separable random phase approximation (SRPA) method and specify it for Skyrme forces with pairing for the case of axially symmetric deformed nuclei. The factorization of the residual interaction allows diagonalization of high-ranking RPA matrices to be avoided, which dramatically reduces the computational expense. This advantage is crucial for the systems with a huge configuration space, first of all for deformed nuclei. SRPA self-consistently takes into account the contributions of both time-even and time-odd Skyrme terms as well as of the Coulomb force and pairing. The method is implemented to describe isovector E1 and isoscalar E2 giant resonances in a representative set of deformed nuclei: $^{154}\mathrm{Sm}$, $^{238}\mathrm{U}$, and $^{254}\mathrm{No}$. Four different Skyrme parameterizations (SkT6, SkM${}^{*}$, SLy6, and SkI3) are employed to explore the dependence of the strength distributions on some basic characteristics of the Skyrme functional and nuclear matter. In particular, we discuss the role of isoscalar and isovector effective masses and their relation to time-odd contributions. The high sensitivity of the right flank of E1 resonance to different Skyrme forces and the related artificial structure effects are analyzed.

Self-consistent separable random-phase approximation for Skyrme forces: Giant resonances in axial nuclei

Time-odd densities and their effect on electric giant resonances are investigated within the self-consistent separable random-phase-approximation (SRPA) for a variety of Skyrme forces (SkT6, SkO, SkM*, SIII, SGII, SLy4, SLy6, SkI3). Time-odd densities are essential for maintaining the Galilean invariance of the Skyrme functional. Their contribution is determined by the values and signs of the isovector and isoscalar effective-mass parameters of the force. In even-even nuclei these densities are not active in the ground state but can affect the dynamics. As a particular case, we explore the role of the current density in the description of isovector E1 and isoscalar E2 giant resonances in a chain of spherical and deformed Nd isotopes with A=134-158. The relation of the current to the effective masses and relevant parameters of the Skyrme functional is analyzed. It is shown that the current contributes substantially to E1 and E2 and the contribution is the same for all the isotopes along the chain, i.e. for both standard and exotic nuclei.

http://www-ucjf.troja.mff.cuni.cz/~vesely/papers/papers/Int.%20J.%20Mod.%20Phys.E,%2017.pdf

Tddft with skyrme forces: effect of time-odd densities on electric giant resonances

We propose a method for solving exactly the nuclear eigenvalue problem within a multiphonon space constructed out of Tamm-Dancoff phonons. The method consists in deriving, within a given n-phonon subspace, a set of equations, of simple structure for any n, which are solved iteratively, starting from the particle-hole vacuum, to yield a set of states covering a multiphonon space up to an arbitrary number of phonons. The intrinsic redundancy of the set so generated is removed completely and exactly by a simple and efficient prescription. Such a multiphonon basis reduces the Hamiltonian into diagonal blocks plus residual off-diagonal terms of simple form. Its diagonalization becomes straightforward and yields exact eigensolutions. {sup 16}O is adopted as numerical test ground.

J. Kvasil

Papers

Spin-flip M1 giant resonance as a challenge for Skyrme forces

Separable random phase approximation for self-consistent nuclear models

Self-consistent separable random-phase approximation for Skyrme forces: Giant resonances in axial nuclei

Tddft with skyrme forces: effect of time-odd densities on electric giant resonances

Exact formulation and solution of the nuclear eigenvalue problem in a microscopic multiphonon space