  The PASER is potentially a very attractive method for particle acceleration,
in which energy from an active medium is transferred to a charged particle
beam. The effect is similar to the action of a maser or laser with the
stimulated emission of radiation being produced by the virtual photons in the
electromagnetic field of the beam. We have been investigating the possibility
of developing a demonstration PASER operating at X-band. The less restrictive
beam transport and device dimensional tolerances required for working at X-band
rather than optical frequencies as well as the widespread application of X-band
hardware in accelerator technology all contribute to the attractiveness of
performing a PASER demonstration experiment in this frequency range. Key to
this approach is the availability of a new class of active materials that
exhibit photoinduced electron spin polarization. We will report on the status
of active material development and measurements, numerical simulations, and
progress towards a planned microwave PASER acceleration experiment at the
Argonne Wakefield Accelerator facility.
