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Abstract: In this paper, we report on internal conversion coefficients for to superheavy elements obtained from relativistic Dirac–Fock calculations. The effect of the atomic vacancy created during the conversion process has been taken into account using the so called “Frozen Orbital” approximation. The selection of this atomic model is supported by our recent comparison of experimental and theoretical conversion coefficients across a wide range of nuclei. The atomic masses, valence shell electron configurations, and theoretical atomic binding energies required for the calculations were adopted from a critical evaluation of the published data. The new conversion coefficient data tables presented here cover all atomic shells, transition energies from 1 keV up to 6000 keV, and multipole orders of 1–5. A similar approach was used in our previous calculations [T. Kibédi, T.W. Burrows, M.B. Trzhaskovskaya, P.M. Davidson, C.W. Nestor Jr., Nucl. Instrum. Methods Phys. Res. A 589 (2008) 202] for . [Copyright &y& Elsevier]

Abstract: Adopted spectroscopic information on pure E0 transitions has been deduced by critical evaluation of the available experimental data for all even–even nuclei ranging from to . Values of , the ratio of the K-conversion electron intensity of the , E0 transition to that of the , E2 transition, have been determined. This procedure, together with the most recent theoretical coefficients for internal conversion and electron–positron pair creation, as well as electronic factors, produced a large number of new X(E0/E2) values, defined as the dimensionless ratio of the absolute B(E0) and B(E2) transition rates. The squared value of the monopole transition strength, ρ 2(E0), has been deduced using the best available 0+-level half-lives and branching ratios. [Copyright &y& Elsevier]

A previous compilation of excitation energies Ex (31−) and reduced electric-octupole transition probabilities B(E3;01+→31−) for first 3− states of even-even nuclides, which covered the literature to March 1988, has been updated to cover the literature to the end of 2000. Data obtained from various experimental procedures are tabulated. The final table presents adopted values of B(E3;01+→31−), together with the E3 transition strengths &z.sfnc;M(E3)&z.sfnc;2 in Weisskopf units. Plots of &z.sfnc;M(E3)&z.sfnc;2 versus mass number A, atomic number Z, and neutron number N confirm the existence of structure suggested in the earlier work. [Copyright &y& Elsevier]

A new tabulation of electronic factors is reported for electron conversion for elements of Z from 5 to 126 and electronic factors for electron–positron pair conversion for elements of even Z from 4 to 100. The electronic factors for electron conversion, Ω C E (E0), were calculated using a modified version of the CATAR program developed by Pauli and Raff with a relativistic-Hartree–Fock–Slater approach (Pauli and Raff, 1975). The electronic factors for electron–positron pair conversion, Ω I P F (E0), were calculated using the model developed by Wilkinson (1969). The data tables presented here cover all atomic shells up to R2 and transition energies from 1 keV to 6000 keV and from 1100 keV to 8000 keV for pair conversion. A comparison with previous electronic factor tabulations is presented. Ratios of experimental Ω (E0) values for 83 E0 transitions in 8 ≤ Z ≤ 98 are compared to this tabulation. Two examples of how to use the tabulation to extract E0 strengths are also included. [ABSTRACT FROM AUTHOR]

Spectroscopic information on the decay properties of high- K isomers in deformed and transitional nuclei has been evaluated and collated. Assigned multi-quasiparticle configurations are included. Factors that control the transitions strengths, such as various contributions to K mixing, are outlined. The systematics of K -forbidden transitions for different multipolarities are discussed for selected cases in terms of the hindrances, F W , and of the reduced hindrance factor per degree of K forbiddenness, f ν , where ν = | Δ K − λ | , Δ K is the K -value difference between the initial and final state and λ is the transition multipole order. With the improved statistics for E 1 , M 1 and E 2 transitions, a factorization into the product of the underlying multipolarity-dependent transition strength and a ν -dependence, due to K forbiddenness ( f 0 ), is possible. This suggests a weaker dependence on K forbiddenness than is commonly assumed. [ABSTRACT FROM AUTHOR]