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Large-scale fission barrier calculations have been performed in the framework of the Skyrme-Hartree-Fock model. Our Hartree-Fock-Bogoliubov calculations restore broken symmetries such as translational invariance, particle-number conservation, parity, and, in a more approximate way, rotational invariance. Axial symmetry is imposed, but reflection asymmetry is allowed. The energy surface properties are analyzed with the flooding method. A large set of Skyrme interactions, which were fitted to all known masses under different specific constraints, is used to study the main effects influencing the energy surface and the barrier heights. The principal interaction used in the comparison with experimental barriers is BSk8, the force on which the HFB-8 mass table is based. We found that for nuclei with 92 Z 98 the agreement of our calculations with experimental data is excellent; the rms deviation on the primary barriers is 0.722 MeV. For lighter nuclei, however, the calculated primary barriers are always too high because of the existence of a third barrier at very high deformations. However, our calculated superheavy barriers appear to be too low, although they are consistent with previous calculations.

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We test the charge-radius predictions of two modern mass formulas. Comparing with the charge-radius data for the 523 nuclei listed in the compilation of Nadjakov et al. ͓At. Data Nucl. Data Tables 56, 133 ͑1994͔͒ it has been found that the finite-range droplet model mass formula leads to an rms deviation of 0.045 fm. The corresponding quantity for the Skyrme-Hartree-Fock mass formula HFBCS-1 is 0.024 fm.Since different nuclear-mass formulas that give similar fits to the mass data can extrapolate quite differently out to the unknown regions of the nuclear chart close to the neutron-drip line ͑see, for example, Refs. ͓1,2͔͒, the question arises as to how one might assess the relative reliabilty of the different formulas. ͑The question is particularly acute in the astrophysical context, since the evolution of the r process of nucleosynthesis is sensitive to the masses of precisely these unknown nuclei.͒ One obvious test is to check how the different formulas perform for newly acquired mass data, but while surviving this test is clearly a necessary condition it is not very stringent in practice, since the new data tend to lie too close to the stability line to discriminate between the different formulas.Another way of probing the underlying models is to look at the predictions made for some other measurable quantity, not included in the original fit, and in this respect rms charge radii serve as an excellent test, since many nuclei have been measured with great accuracy. This approach was adopted by Buchinger et al. in Ref. ͓3͔ to compare what were at that time the two most recently constructed global mass formulas, the 1988 version of the FRDM ͑finite-range droplet model͒ ͓4͔ and the ETFSI-1 ͑extended Thomas-Fermi plus Strutinsky integral͒ ͓5,6͔ formulas; the former was then the most sophisticated version of the macroscopic-microscopic approach to mass formulas, while the latter was the first mass formula to be based entirely on microscopic forces, a semiclassical approximation to the Hartree-Fock ͑HF͒ method for Skyrme forces being used.The present paper is essentially an update to that paper, intended to take account of the following developments that have taken place in the intervening eight years: ͑i͒ a new version of the FRDM was published in 1995 ͓7͔; ͑ii͒ a true HF mass formula, HFBCS-1, without any semi-classical approximation, was constructed for the first time ͓8,9͔; ͑iii͒ a much more extensive compilation of charge-radius data became available ͓10͔. Specifically, we compare the chargeradius predictions given by the 1995 FRDM and the HFBCS-1 mass formulas with this newer data compilation.The 1995 FRDM table ͓7͔, like the 1988 table ͓4͔, could have given the charge radii for all the tabulated nuclei, but did not. However, by making use of the paper of Myers and Schmidt ͓11͔, we have calculated the new FRDM rms charge radii from the published values of the new model parameters and the tabulated deformation parameters, exactly as in our 1994 paper ͓3͔, which should be consulted for all details.Here we recall...

† This article contains part of the experimental work performed during Teigelhöfer's Ph.D. thesis. ‡ Deceased.