  The use of electron beams is ubiquitous; electron microscopy, scanning
tunneling microscopy, electron lithography, and electron diffractometry all use
well-collimated and focused beams. On the other hand, quantum degenerate
electron beams do currently not exist. The realization of such beams may impact
all electron beam technologies and are interesting to pursue. Past attempts to
reach degeneracy were hampered by the low degeneracy of continuously emitting
electron sources. With the recent advent of ultra-short electron pulses, high
degeneracy is expected. Coulomb repulsion and low quantum coherence are hurdles
that need to be overcome. A quantum analysis of the electron degeneracy for
partially coherent pulsed electron sources is presented. Two-particle
coincidence spectra are obtained for source parameters that are currently
available. The conclusive demonstration of the fermionic Hanbury-Brown Twiss
(HBT) effect for free electrons is shown to be within reach, and our results
support the claim that femto-second nanotip electron sources, both polarized
and unpolarized, can manifest partial to complete quantum degeneracy with
appreciable signal-to-noise-ratios for free electron pulses notwithstanding
their small particle numbers.
