Giant monopole resonance in Sn and Sm nuclei and the compressibility of nuclear matter.

Abstract

A study of the systematics of the breathing mode giant monopole resonance in the isotopic chains of Sn and Sm nuclei by means of inelastic scattering of 120 MeV alpha particles at 0\ifmmode^\circ\else\textdegree\fi{} has been performed. The obtained energy systematics for spherical Sn and Sm nuclei have been employed to fit the nuclear-compressibility parameters. The data on Sn and Sm nuclei have been used in conjunction with already existing data on $^{208}\mathrm{Pb}$ and $^{24}\mathrm{Mg}$ to constrain the various parameters contributing to the nuclear compressibility. The compressibility of nuclear matter ${K}_{\ensuremath{\infty}}$ has been deduced to be 300\ifmmode\pm\else\textpm\fi{}25 MeV, in contrast with the commonly accepted value of 210\ifmmode\pm\else\textpm\fi{}30 MeV. The neutron-asymmetry term has been determined to be -320\ifmmode\pm\else\textpm\fi{}180 MeV.