Collective excitations in neutron-star crusts

We explore the spectrum of low-energy collective excitations in the crust of a neutron star, especially in the inner region where neutron-proton clusters are immersed in a sea of superfluid neutrons. The speeds of the different modes are calculated systematically from the nuclear energy density functional theory using a Skyrme functional fitted to essentially all experimental atomic mass data.
Comment: 5 pages, 1 figure, proceeding of the Nuclear Physics in Astrophysics VI conference, Lisbon, May 19-24 2013