\contentsline {chapter}{\numberline {4}Photon Beam}{2}
\contentsline {section}{\numberline {4.1}Choice of technique}{3}
\contentsline {subsection}{\numberline {4.1.1}Compton back-scatter}{4}
\contentsline {subsection}{\numberline {4.1.2}Tagged bremsstrahlung}{6}
\contentsline {subsection}{\numberline {4.1.3}Coherent bremsstrahlung}{7}
\contentsline {section}{\numberline {4.2}Photon Source}{9}
\contentsline {subsection}{\numberline {4.2.1}Essential features}{11}
\contentsline {subsection}{\numberline {4.2.2}Use of collimation}{12}
\contentsline {subsection}{\numberline {4.2.3}Choice of radiator}{18}
\contentsline {subsection}{\numberline {4.2.4}Crystal thickness}{21}
\contentsline {subsection}{\numberline {4.2.5}Crystal mount}{22}
\contentsline {subsection}{\numberline {4.2.6}Crystal quality and lifetime}{24}
\contentsline {section}{\numberline {4.3}Electron Beam}{25}
\contentsline {subsection}{\numberline {4.3.1}Beam emittance requirements}{26}
\contentsline {subsection}{\numberline {4.3.2}Electron beam line optics}{29}
\contentsline {subsection}{\numberline {4.3.3}Electron beam dump}{29}
\contentsline {section}{\numberline {4.4}Tagging Spectrometer}{30}
\contentsline {subsection}{\numberline {4.4.1}Magnet}{30}
\contentsline {subsection}{\numberline {4.4.2}Spectrometer Optics}{32}
\contentsline {subsection}{\numberline {4.4.3}Focal-plane hodoscope}{32}
\contentsline {section}{\numberline {4.5}Operating Beam Intensity}{35}