Nuclear properties according to the Thomas-Fermi model

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In order to formulate a statistical model of nuclear properties we combine the Thomas-Fermi assumption of two fermions per h 3 of phase space with an effective interaction between nucleons that contains seven adjustable parameters. After allowing for shell effects, an even-odd correction and a congruence energy (“Wigner Term”), six of the seven parameters were fitted to 1654 ground state masses of nuclei with N , Z ⩾ 8, together with a constraint that ensures agreement with measured values of the nuclear surface diffuseness. The RMS deviation in the fit to masses was 0.655 MeV, and the calculated values exhibit no drastic discrepancies even for A = 3. Calculated sizes of nuclear charge distributions agree closely with measurements. Calculated fission barriers were compared with 40 measured values down to 75 Br. For Z ⩾ 88 the agreement is almost perfect. For Z < 88 the trend of the measurements seems to confirm the expectation that the congruence energy should double its magnitude for strongly necked-in saddle-point shapes. A seventh (density-dependence) parameter in the effective interaction can be adjusted to ensure fair agreement with the measured energy-dependence of the optical model potential in the range from −70 MeV to 180 MeV. The model is used to predict properties of nuclear and neutron matter (including their compressibilities). A table of some 9000 calculated ground state masses of nuclei up to Z = 135 has been prepared.