Response of asymmetric nuclear matter to isospin-flip probes

We investigate the RPA response of asymmetric nuclear matter to external fi elds which induce charge exchange between nucleons, both at zero and finite temperature. Closed expressions are obtained for the RPA response in each spin channel when the nucleon-nucleon interaction is of the Skyrme type. Ex change terms are fully taken into account. We consider the transferred mome ntum, asymmetry and temperature as the relevant parameters of our study. Sp ecial emphasis is given to the role of neutron excess in relation to the co llective states at low momentum. (C) 1999 Elsevier Science B.V. All rights reserved.