LCLS Conceptual Design Report - Stanford Synchrotron Radiation ...

L C L S C O N C E P T U A L D E S I G N R E P O R T
distributions of the radiation at the undulator exit are shown in Figure 4.7 and Figure 4.8, for the
same case.
Figure 4.7 Angular distribution of the radiation at the undulator exit, showing a single Gaussian
mode, with an rms aperture of about 2 µrad.
Filtering and focusing the radiation and transporting it to the experimental areas is a
challenge. A normal incidence mirror at 100 m would see an energy flux density of about 1 J/cm 2 ,
about 1 eV/atom. The large power density of the LCLS x-ray pulses will push the optical
elements and instrumentation into a new strong field regime, but also offers new opportunities for
scientific research. The development of x-ray optics to handle these large power densities is
described in Chapter 9 of this CDR.
Figure 4.8 Spectral power distribution at undulator exit.
4-18 ♦ F E L P H Y S I C S