No abstract

Multipole strength distributions for isoscalar L ≤ 2 transitions in 28 Si have been extracted using 386-MeV inelastic α scattering at extremely forward angles, including 0• . Observed strength distributions are in good agreement with microscopic calculations for an oblate-deformed ground-state. In particular, a large peak at an excitation energy of 17.7 MeV in the isoscalar giant monopole resonance (ISGMR) strength is consistent with the calculations.

No abstract

The isoscalar giant monopole resonance (ISGMR) strength distribution in 24 Mg has been determined from background-free inelastic scattering of 386-MeV α particles at extreme forward angles, including 0 • .

The isoscalar giant monopole resonance (ISGMR) in even-A Cd isotopes has been studied by inelastic α-scattering at 100 MeV/u and at extremely forward angles, including 0• . The asymmetry term in the nuclear incompressibility extracted from the ISGMR in Cd isotopes is found to be Kτ = −555±75 MeV, confirming the value previously obtained from the Sn isotopes. ISGMR strength has been computed in relativistic RPA using NL3 and FSUGold effective interactions. Both models significantly overestimate the centroids of the ISGMR strength in the Cd isotopes. Combined with other recent theoretical effort, the question of the "softness" of the open-shell nuclei in the tin region remains open still.The equation of state (EOS) of nuclear matter plays an important role in our understanding of a number of interesting phenomena such as the collective behavior of nucleons in the nuclei, the massive stellar collapse leading to a supernova explosion, nuclear properties including the neutron-skin thickness of heavy nuclei, and the radii of neutron stars [1, 2]. The nuclear incompressibility, K ∞ , is the curvature of EOS of nuclear matter at saturation density [3]. K ∞ is, thus, a measure of nuclear stiffness and thereby imposes significant constraints on theoretical descriptions of the effective nuclear interactions. However, even more stringent constraints emerge as one studies the evolution of the incompressibility coefficient as the system becomes neutron rich. Neutron-rich systems are sensitive to the poorly-known density dependence of the symmetry energy and the experiments reported here are of vital importance in this regard.The study of the isoscalar giant monopole resonance (ISGMR) provides a direct experimental tool to study nuclear incompressibility in finite nuclear systems. The centroid energy of ISGMR, E ISGMR , can be directly related to the nuclear incompressibility of finite nuclear matter, K A , as:where, m is the nucleon mass and < r 2 > is the mean square radius of the nucleus [4,5]. K A may be further