NUCLEAR PROPERTIES ACCORDING TO THE THOMAS-FERMI MODEL

In order to formulate a statistical model of nuclear properties we com bine the Thomas-Fermi assumption of two fermions per h(3) of phase spa ce with an effective interaction between nucleons that contains seven adjustable parameters. After allowing for shell effects, an even-odd c orrection and a congruence energy (''Wigner Term''), six of the seven parameters were fitted to 1654 ground state masses of nuclei with N, Z greater than or equal to 8, together with a constraint that ensures a greement with measured values of the nuclear surface diffuseness. The RMS deviation in the fit to masses was 0.655 MeV, and the calculated v alues exhibit no drastic discrepancies even for A = 3. Calculated size s of nuclear charge distributions agree closely with measurements. Cal culated fission barriers were compared with 40 measured values down to Br-75. For Z greater than or equal to 88 the agreement is almost perf ect. For Z < 88 the trend of the measurements seems to confirm the exp ectation that the congruence energy should double its magnitude for st rongly necked-in saddle-point shapes. A seventh (density-dependence) p arameter in the effective interaction can be adjusted to ensure fair a greement with the measured energy-dependence of the optical model pote ntial in the range from -70 MeV to 180 MeV. The model is used to predi ct properties of nuclear and neutron matter (including their compressi bilities). A table of some 9000 calculated ground state masses of nucl ei up to Z = 135 has been prepared.