Phase corrections for synchrotron radiation

High accuracy calculations of synchrotron radiation (SR) emitted by a relat ivistic electron show that the phase of the frequency domain electric field of SR differs from the phase of radiation of a virtual point source. These differences may result in the reduction of focusing efficiency of diffract ion-limited SR. if the focusing is performed by conventional optical compon ents optimised for point sources. We show that, by applying a phase correct ion locally, one may transform the phase of SR electric field at a desired polarisation to that of a point source. Such corrections are computed for u ndulator and bending magnet radiation. (C) 2001 Elsevier Science B.V. All r ights reserved.