\relax \emailauthor{somov@jlab.org}{A.Somov\corref {cor1}} \Newlabel{erphy}{a} \Newlabel{cua}{b} \Newlabel{jlab}{c} \Newlabel{mephi}{d} \Newlabel{regina}{e} \Newlabel{uncw}{f} \Newlabel{ncat}{g} \Newlabel{duke}{h} \@LN@col{1} \Newlabel{notice}{1} \Newlabel{cor1}{1} \@writefile{toc}{\contentsline {section}{\numberline {1}Introduction}{1}} \@LN@col{2} \@writefile{toc}{\contentsline {section}{\numberline {2}PrimEx $\eta $ experiment with the GlueX detector}{1}} \@LN@col{1} \@writefile{lof}{\contentsline {figure}{\numberline {1}{\ignorespaces Schematic layout of the GlueX detector (not to scale). 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