On the surface energy of compressible nuclei

The specific nuclear surface energy σ as a function of the central density n_c is shown to behave in a way opposite to that of the saturation curve; in particular, σ is maximum at the saturation density. Starting from the energy of a compressible nucleus, we find after deriving a simple expression for the second derivative of σ, a formula for thecompressibility modulus K_A of finite nuclei which contains, besides the saturation density and the bulk value K_∞, only some well-known surface parameters.