\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} \citation{popov} \@LN@col{1} \@writefile{lof}{\contentsline {figure}{\numberline {1}{\ignorespaces Calorimeter module.}}{2}} \newlabel{fig:ccal_module}{{1}{2}} \@writefile{toc}{\contentsline {section}{\numberline {2}Compton calorimeter of the PrimEx $\eta $ experiment}{2}} \newlabel{sec_ccal}{{2}{2}} \@writefile{toc}{\contentsline {subsection}{\numberline {2.1}Module design}{2}} \@writefile{toc}{\contentsline {subsection}{\numberline {2.2}Calorimeter Design}{2}} \@LN@col{2} \@writefile{lof}{\contentsline {figure}{\numberline {2}{\ignorespaces Schematic layout of the Compton calorimeter.}}{2}} \newlabel{fig:ccal_design}{{2}{2}} \@writefile{toc}{\contentsline {subsection}{\numberline {2.3}Electronics}{2}} \citation{fadc250} \@LN@col{1} \@writefile{toc}{\contentsline {subsection}{\numberline {2.4}Light Monitoring System}{3}} \@writefile{toc}{\contentsline {subsection}{\numberline {2.5}Calibration}{3}} \@LN@col{2} \@writefile{lof}{\contentsline {figure}{\numberline {3}{\ignorespaces Schematic layout of the GlueX detector.}}{3}} \newlabel{fig:pmt_pulse}{{3}{3}} \@writefile{lof}{\contentsline {figure}{\numberline {4}{\ignorespaces Typical flash ADC signal waveform in the calorimeter module.}}{3}} \newlabel{fig:pmt_pulse}{{4}{3}} \@writefile{toc}{\contentsline {subsection}{\numberline {2.6}Performance during PrimEx run}{3}} \@LN@col{1} \@writefile{lof}{\contentsline {figure}{\numberline {5}{\ignorespaces Flash ADC signal amplitudes induced by the LED and $\alpha $-source in the reference PMT.}}{4}} \newlabel{fig:reference_amp}{{5}{4}} \@writefile{lof}{\contentsline {figure}{\numberline {6}{\ignorespaces The ratio of LED to $\alpha $-source signals for different run periods.}}{4}} \newlabel{fig:led_stability}{{6}{4}} \@writefile{toc}{\contentsline {subsubsection}{\numberline {2.6.1}Compton reconstruction}{4}} \@writefile{toc}{\contentsline {section}{\numberline {3}Upgrade of the GlueX forward calorimeter}{4}} \@LN@col{2} \@writefile{lof}{\contentsline {figure}{\numberline {7}{\ignorespaces Typical signal amplitudes in calorimeter modules induced by an LED for different PrimEx $\eta $ run periods. 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