LAL, Orsay, France
JAI, Oxford, United Kingdom
The rapid developments in the field of laser-driven particle acceleration hold the prospect of intense, highly relativistic electron bunches that are only a few fs long. The determination of the temporal profile of such a bunch presents new challenges. The use of a radiative process such as Smith-Purcell radiation (SPR), whereby the beam is made to radiate a small amount of e/m radiation and the temporal profile is then reconstructed from the measured spectral distribution of the radiation, is particularly promising in this respect. We summarize the advantages of SPR and present the design parameters of a forthcoming experiment at the FACET facility at SLAC with bunch lengths of the order of 60fs rms. We also discuss a new approach to the problem of the recovery of the ‘missing phase’, which is essential for the accurate reconstruction of the bunch profile.
