Slow antiprotons in an extended electron system: the one-particle aspects of complete screening

A partially linearized response theory of the Thomas-Fermi-Weizsacker scree ning is used to study charged particles interacting with jellium. This simp le theory can be derived by linearizing contributions involving the Thomas- Fermi kinetic energy-density. The calculations are based on a nonlinear inh omogeneous integrodifferential equation which includes the potential along the lines suggested by the original Thomas-Fermi-Weizsacker theory. The coe fficient of the von Weizsacker term is prescribed according to Kato's cusp condition. This theoretical framework is applied to compute the stopping po wer of a jellium for slow antiprotons and phase-shifts sums of Friedel and Zwerger for the complete screening in an extended system. Illustrative resu lts are presented and discussed. (C) 2000 Elsevier Science B.V. All rights reserved.