Incompressibility of nuclear matter from the giant monopole resonance

EO strength distributions in Zr-90, Sn-116, Sm-144, and Pb-208 have been me asured with inelastic scattering of 240-MeV alpha particles between 0 degre es less than or equal to theta(lab) less than or equal to 6 degrees to grea ter precision than previously available. In Sn, Sm, and Pb, EO strength was concentrated in approximately symmetric peaks, whereas in Zr-90 it had a s ignificant high energy tail. Comparing with microscopic calculations using the Gogny interaction, these and our previously reported results for Ca-40 are consistent with a nuclear matter incompressibility of 231 +/- 5 MeV. Pr evious data gave an average of 215 MeV and the value for different nuclei d isagreed by up to 40 MeV.