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\@writefile{toc}{\contentsline {section}{\numberline {I}Introduction}{1}{}}
\@writefile{toc}{\contentsline {section}{\numberline {II}photon beam simulation}{2}{}}
\@writefile{toc}{\contentsline {section}{\numberline {III}Conclusions}{2}{}}
\bibstyle{apsrev}
\@writefile{lof}{\contentsline {figure}{\numberline {1}{\ignorespaces Cut-away view of the collimator with the steel insert, as defined in the Monte Carlo geometry used for this study. The beam enters from the left in this figure, and passes through the 5-mm hole in the active collimator (the left half of the figure) before reaching the front face of the primary tungsten collimator located at the vertical midplane in the figure. The inner steel insert is inside a 5-mm hole through a tungsten block, which in turn is placed inside the larger lead collimator that surrounds it. The figure shows a beam photon that interacts in the steel collimator and generates a shower that gets absorbed in the collimator material.}}{3}{}}
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\@writefile{lof}{\contentsline {figure}{\numberline {2}{\ignorespaces  Simulated photon beam spectrum for all photons exiting the diamond radiator (left) and for all photons that reach the GlueX liquid hydrogen target (right) with the steel insert installed in the 5-mm tungsten primary collimator. }}{4}{}}
\newlabel{beamspectra}{{2}{4}{}{}{}}
\@writefile{lof}{\contentsline {figure}{\numberline {3}{\ignorespaces  Spectrum of the 3\% of all particles in the photon beam that reach the GlueX liquid hydrogen target, having been generated through interactions somewhere between the radiator and the GlueX target. Of these, 95\% are photons, with the remainder being mostly electrons and positrons. The energy spectrum of the charged 5\% component is similar in shape to the one shown above for the aggregate. }}{4}{}}
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\@writefile{lof}{\contentsline {figure}{\numberline {4}{\ignorespaces  Transverse impact distribution of all particles in the photon beam reaching the GlueX liquid hydrogen target (left) and only those over 500 MeV (right). Photons are shown by blue points, and charged particles with red points. In the left plot, 84\% of all impacts are within the innermost intense dot. In the right plot, the corresponding fraction is 97\%, increasing to 98\% if the low-energy cutoff is raised to 2\nobreakspace  {}GeV. }}{5}{}}
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