English

Dispersion in a relativistic degenerate electron gas

Plasma Physics 2009-11-11 v1

Abstract

Relativistic effects on dispersion in a degenerate electron gas are discussed by comparing known response functions derived relativistically (by Jancovici) and nonrelativistically (by Lindhard). The main distinguishing feature is one-photon pair creation, which leads to logarithmic singularities in the response functions. Dispersion curves for longitudinal waves have a similar tongue-like appearance in the relativistic and nonrelativistic case, with the main relativistic effects being on the Fermi speed and the cutoff frequency. For transverse waves the nonrelativistic treatment has a nonphysical feature near the cutoff frequency for large Fermi momenta, and this is attributed to an incorrect treatment of the electron spin. We find (with two important provisos) that one-photon pair creation is allowed in superdense plasmas, implying relatively strong coupling between transverse waves and pair creation.

Keywords

Cite

@article{arxiv.physics/0603227,
  title  = {Dispersion in a relativistic degenerate electron gas},
  author = {J. McOrist and D. B. Melrose and J. I. Weise},
  journal= {arXiv preprint arXiv:physics/0603227},
  year   = {2009}
}

Comments

17 pages, 9 figures. Submitted to Physical Review E