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finish discussion
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@ -44,6 +44,8 @@ captions=nooneline,captions=tableabove,english,DIV=16,numbers=noenddot,final]{sc
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\input{./tex/pheno/setup.tex}
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\input{./tex/pheno/setup.tex}
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\input{./tex/pheno/discussion.tex}
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\input{./tex/pheno/discussion.tex}
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\input{./tex/summary.tex}
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\clearpage
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\clearpage
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\appendix
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\appendix
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\pagenumbering{roman}
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\pagenumbering{roman}
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@ -53,7 +53,8 @@ otherwise. The fine structure constant's value \(\alpha = 1/137.036\)
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is configured in \sherpa\ and used in analytic calculations.
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is configured in \sherpa\ and used in analytic calculations.
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The compatibility of histograms is tested as discussed in
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The compatibility of histograms is tested as discussed in
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\cref{sec:comphist}.
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\cref{sec:comphist} and the respective \(P\) and \(T\) values are
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being included in the ratio plots.
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\section{Source Code}%
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\section{Source Code}%
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\label{sec:source}
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\label{sec:source}
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@ -9,12 +9,12 @@
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Monte Carlo methods for multidimensional integration and sampling of
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Monte Carlo methods for multidimensional integration and sampling of
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probability distributions are central tools of modern particle
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probability distributions are central tools of modern particle
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physics. Therefore some simple methods and algorithms are being
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physics. Therefore some simple methods and algorithms are being
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studied and implemented here and will be applied to the results from
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studied and implemented from scratch here and will be applied to the
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\cref{chap:qqgg}. The \verb|python| code for the implementation can be
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results from \cref{chap:qqgg}. The \verb|python| code for the
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found as described in \cref{sec:source}. The sampling and integration
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implementation can be found as described in \cref{sec:source}. The
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intervals, as well as other parameters have been chosen as in
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sampling and integration intervals, as well as other parameters have
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\cref{sec:compsher} been chosen, so that \result{xs/python/eta} and
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been chosen as in \cref{sec:compsher} been chosen, so that
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\result{xs/python/ecm}. This chapter is based on the
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\result{xs/python/eta} and \result{xs/python/ecm}. This chapter is
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appendix~\cite{buckley:2011ge} and supplants that source with some
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based on the appendix~\cite{buckley:2011ge} and supplants that source
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derivations and more methods like the \vegas~\cite{Lepage:19781an}
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with some derivations and more methods like the
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algorithm.
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\vegas~\cite{Lepage:19781an} algorithm.
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@ -136,18 +136,22 @@ code. The resulting histograms of some observables are depicted in
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\result{xs/python/pdf/samp_eff} using a total of
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\result{xs/python/pdf/samp_eff} using a total of
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\result{xs/python/pdf/num_increments} hypercubes.
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\result{xs/python/pdf/num_increments} hypercubes.
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The distributions are more or less compatible with each other
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The histograms are more or less compatible with each other
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\footnote{See \cref{sec:comphist} for a description of the
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\footnote{See \cref{sec:comphist} for a description of the
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compatibility test.}. In all cases the difference between
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compatibility test.}. In all cases the difference between
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\(T\)-Value and the mean of the \(\chi^2\) distribution for that value
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\(T\)-Value and the mean of the \(\chi^2\) distribution for that value
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(\(=50\), the number of bins) is less then the standard deviation
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(\(=50\), the number of bins) is less then the standard deviation
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(\(=10\)) of the same distribution and thus the histograms are
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(\(=10\)) of the same distribution and thus the histograms are
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considered compatible. The very steep distributions for \(\pt\) and
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considered compatible. The angular distributions for
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\(m_{\gamma\gamma}\) are especially sensitive to fluctuations and the
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\(\eta, \cos\theta\) show agreeable \(P\)-values, but the very steep
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systemic errors introduced of the weight of each hypercube. Therefore
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distributions for \(\pt\) and \(m_{\gamma\gamma}\) are especially
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their formal measure of compatibility, the \(P\)-Value, is rather
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sensitive to fluctuations and the systemic errors introduced of the
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low. This shows that the error in the determination of the weights for
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weight of each hypercube. Therefore their formal measure of
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the hypercubes should be studied more carefully.
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compatibility, the \(P\)-Value, is rather low. This indicates that the
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MC error in the determination of the weights for the hypercubes should
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be studied more carefully and highlights the disadvantage of the
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sampling method chosen here. The kinematics and PDF values were
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compared with sherpa and proved to be equivalent.
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The \sherpa\ runcard utilized here and the analysis used to produce
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The \sherpa\ runcard utilized here and the analysis used to produce
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the histograms can be found in
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the histograms can be found in
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@ -19,33 +19,13 @@
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\begin{figure}[ht]
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\begin{figure}[ht]
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\centering
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\centering
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\begin{subfigure}[t]{.49\textwidth}
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\rivethist{pheno/cos_theta}
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\caption{\label{fig:disc-cos_theta}}
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\end{subfigure}
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\begin{subfigure}[t]{.49\textwidth}
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\rivethist{pheno/eta}
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\caption{\label{fig:disc-eta}}
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\end{subfigure}
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\begin{subfigure}[t]{.49\textwidth}
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\begin{subfigure}[t]{.49\textwidth}
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\rivethist{pheno/total_pT}
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\rivethist{pheno/total_pT}
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\caption{\label{fig:disc-total_pT}}
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\caption{\label{fig:disc-total_pT}}
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\end{subfigure}
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\end{subfigure}
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\begin{subfigure}[t]{.49\textwidth}
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\begin{subfigure}[t]{.49\textwidth}
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\rivethist{pheno/inv_m}
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\rivethist{pheno/azimuthal_angle}
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\caption{\label{fig:disc-inv_m}}
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\caption{\label{fig:disc-azimuthal_angle}}
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\end{subfigure}
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\begin{subfigure}[t]{.49\textwidth}
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\rivethist{pheno/o_angle}
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\caption{\label{fig:disc-o_angle}}
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\end{subfigure}
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\end{figure}
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%
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\begin{figure}[t]
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\centering \ContinuedFloat
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\begin{subfigure}[t]{.49\textwidth}
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\rivethist{pheno/o_angle_cs}
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\caption{\label{fig:disc-o_angle_cs}}
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\end{subfigure}
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\end{subfigure}
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\begin{subfigure}[t]{.49\textwidth}
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\begin{subfigure}[t]{.49\textwidth}
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\rivethist{pheno/pT}
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\rivethist{pheno/pT}
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@ -56,56 +36,76 @@
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\caption{\label{fig:disc-pT_subl}}
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\caption{\label{fig:disc-pT_subl}}
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\end{subfigure}
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\end{subfigure}
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\begin{subfigure}[t]{.49\textwidth}
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\begin{subfigure}[t]{.49\textwidth}
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\rivethist{pheno/azimuthal_angle}
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\rivethist{pheno/inv_m}
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\caption{\label{fig:disc-azimuthal_angle}}
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\caption{\label{fig:disc-inv_m}}
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\end{subfigure}
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\end{figure}
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%
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\begin{figure}[t]
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\centering \ContinuedFloat
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\begin{subfigure}[t]{.49\textwidth}
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\rivethist{pheno/cos_theta}
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\caption{\label{fig:disc-cos_theta}}
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\end{subfigure}
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\begin{subfigure}[t]{.49\textwidth}
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\rivethist{pheno/eta}
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\caption{\label{fig:disc-eta}}
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\end{subfigure}
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\begin{subfigure}[t]{.49\textwidth}
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\rivethist{pheno/o_angle}
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\caption{\label{fig:disc-o_angle}}
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\end{subfigure}
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\begin{subfigure}[t]{.49\textwidth}
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\rivethist{pheno/o_angle_cs}
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\caption{\label{fig:disc-o_angle_cs}}
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\end{subfigure}
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\end{subfigure}
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\caption{\label{fig:holhistos} Histograms of observables generated
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\caption{\label{fig:holhistos} Histograms of observables generated
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by simulations with increasingly more effects turned on.}
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by simulations with increasingly more effects turned on.}
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\end{figure}
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\end{figure}
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%
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%
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The results of the \sherpa\ runs for each stage with \(10^7\) events
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The results of the \sherpa\ runs for each stage with \(10^7\) events
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each are depicted in the histograms in \cref{fig:holhistos} and shall
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each are depicted in the histograms in \cref{fig:holhistos} and shall
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now be discussed in detail.
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now be discussed in detail.\footnote{A higher precision study was not
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%TODO: high prec not possible
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possible due to unavailability of access to the \emph{Taurus}
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Because of the analysis cuts, the total number of accepted events is
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cluster at the time of writing.} Because of the analysis cuts, the
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smaller than the number of events generated by \sherpa, but sufficient
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total number of accepted events is smaller than the number of events
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for proper statistics for most observables. The fiducial cross
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generated by \sherpa, but sufficient for proper statistics for most
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sections of the different stages, which are compared in
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observables. Also the fiducial cross sections of the different stages,
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\cref{fig:disc-xs}, differ as a result.
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which are compared in \cref{fig:disc-xs}, differ as a result of the
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% TODO: not as result
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NLO effects that have been switched on. All histograms are normalized
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to their respective cross sections.
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All other histograms
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are normalized to their respective cross sections.
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Effects that give the photon system additional $\pt$ decrease the
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Effects that give the photon system additional $\pt$ decrease the
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cross section. This can be understood as follows. When there is no
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cross section This can be understood as follows. When there is no
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additional \(\pt\), then the photon momenta are back to back in the
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additional \(\pt\), then the photon momenta are back to back in the
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plane perpendicular to the beam axis (transverse plane). If the system
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plane perpendicular to the beam axis (transverse plane). Because
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now gets a kick then this usually subtracts \(\pt\) from one of the
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four-momentum conservation is enforced, every emission from a parton
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photons unless that kick is near perpendicular to the photons. Because
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gives a recoil momentum to that parton. If the system now gets a
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the \(\pt\) distribution (\cref{fig:disc-pT,fig:disc-pT_subl}) is very
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recoil from parton showering, then this usually subtracts \(\pt\) from
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steep, a lot of events produce photons with low \(\pt\) and so this
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one of the photons unless that recoil is near perpendicular to the
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effect is substantial. The fraction of events that have been discarded
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photons. Because the \(\pt\) distribution
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by the \(\eta\) and \(\pt\) cuts are plotted in
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(\cref{fig:disc-pT,fig:disc-pT_subl}) is very steep, a lot of events
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\cref{fig:disc-cut-disc}, which shows an increase for all stages after
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produce photons with low \(\pt\) and so this effect is
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\stone, leading (principally) to the drop in cross section for the
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substantial. The fraction of events that have been discarded by the
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\sttwo\ and \stthree.
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\(\eta\) and \(\pt\) cuts are plotted in \cref{fig:disc-cut-disc},
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which shows an increase for all stages after \stone, leading
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(principally) to the drop in cross section for the \sttwo\ and
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\stthree.
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The isolation cuts do affect the cross section as well, as is
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The isolation cuts do affect the cross section as well, as is
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demonstrated in \cref{fig:disc-iso-disc} which shows the fraction of
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demonstrated in \cref{fig:disc-iso-disc} which shows the fraction of
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events discarded due to the isolation cuts. The \stfour\ cross section
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events discarded due to the isolation cuts. The \stfour\ cross section
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is a bit higher than the \stthree\ one, because the hardonization
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is a bit higher than the \stthree\ one, because the hardonization
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favors isolation of photons by reducing the number of particles in the
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favors isolation of photons by reducing the collinearity the of
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final state and clustering them closer together. The opposite effect
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particles in the final state and may create particles like neutrinos
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can be seen with MI, where the number of final state particles is
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that show in the detectors at all or can easily identified
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increased and this effect leads to another substantial drop in the
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(muons). The opposite effect can be seen with MI, where the number of
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cross section.
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final state particles is increased and this effect leads to another
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% TODO: analysis plot of rejected events?
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substantial drop in the cross section.
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% TODO: link to CS frame
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% TODO: iso cuts
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Also the NLO nature of the effects in the stages after \stone\ reduces
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% TODO: hadr isolation? why
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cross section, for instance by ``adding coupling constants'' for each
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% TODO: teilchen aufgefaechert, weniger in cone, teilchen ohne calo
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shower emission or multiple interaction.
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The transverse momentum of the photon system (see
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The transverse momentum of the photon system (see
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\cref{fig:disc-total_pT}) now becomes non trivial, as both the \sttwo\
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\cref{fig:disc-total_pT}) now becomes non trivial, as both the \sttwo\
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@ -115,24 +115,34 @@ involved in the hard process and thus generates transverse momentum
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and primordial \(\pt\) is simulated by the \stthree\ stage. In regions
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and primordial \(\pt\) is simulated by the \stthree\ stage. In regions
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of high \(\pt\) all but the \stone\ stage are largely compatible,
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of high \(\pt\) all but the \stone\ stage are largely compatible,
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falling off steeply at
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falling off steeply at
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\(\mathcal{O}(\SI{10}{\giga\electronvolt})\). In the region of
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\(\mathcal{O}(\SI{10}{\giga\electronvolt})\). Because parton showers
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are modeled in the collienar limit, they cannot necessarily be trusted
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in higher \(\pt\) regions~\cite{buckley:2011ge}.
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The partons in a proton are somewhat localized and thus the
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uncertainty principle demands that those partons have some momentum
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perpendicular to the proton motion. The default parameters in \sherpa\
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assign transverse momenta according to a Gaussian distribution with a
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mean and standard deviation of \gev{.8}. In the region of
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\SI{1}{\giga\electronvolt} and below, the effects primordial \(\pt\)
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\SI{1}{\giga\electronvolt} and below, the effects primordial \(\pt\)
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show as an enhancement in cross section. This is consistent with the
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show as an enhancement in cross section.
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mean of the primordial \(\pt\) distribution which was off the order of
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% The distribution for MI is
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\gev{1}. The distribution for MI is enhanced at very low \(\pt\) which
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% enhanced at very low \(\pt\) which could be an isolation effect or
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could be an isolation effect or stem from the fact, that other partons
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% stem from the fact, that other partons can emit QCD bremsstrahlung and
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can emit QCD bremsstrahlung and showers as well, decreasing the
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% showers as well, decreasing the showering probability for the partons
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showering probability for the partons involved in the hard scattering.
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% involved in the hard scattering.
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% TODO: clarify, Frank
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% TODO: clarify, Frank
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The fact that the distribution has a maximum and falls off towards
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The fact that the distribution has a maximum and falls off towards
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lower \(\pt\) relates to the fact, that parton shower algorithms
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lower \(\pt\) relates to the fact, that parton shower algorithms
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effectively sum over all terms of the perturbation series and is
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effectively sum over all terms of the perturbation
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nontrivial~\cite{buckley:2011ge}.
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series~\cite{buckley:2011ge}.
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Related effects can be seen in the distribution for the azimuthal
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Related effects can be seen in the distribution for the azimuthal
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separation of the photons in \cref{fig:disc-azimuthal_angle}. Albeit
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separation of the photons in \cref{fig:disc-azimuthal_angle}.
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back to back photons are favored by all distributions and most events
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feature an azimuthal separation of less than \(\pi/2\), the
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Back to back photons are favored by all distributions because
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deviations from this configuration are purely NLO effects, so most
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events feature an azimuthal separation of less than \(\pi/2\). The
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enhancement of the low \(\pt\) regions in the \stthree\ stage also
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enhancement of the low \(\pt\) regions in the \stthree\ stage also
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leads to an enhancement in the back-to-back region for this stage over
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leads to an enhancement in the back-to-back region for this stage over
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the \sttwo\ stage.
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the \sttwo\ stage.
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@ -145,23 +155,23 @@ compatible beyond \gev{1}. Again, the effect of primordial \(\pt\)
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becomes visible transverse momenta smaller than \gev{1}.
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becomes visible transverse momenta smaller than \gev{1}.
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% TODO: mention steepness again
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% TODO: mention steepness again
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The \(\pt\) distribution for the sub-leading photon shows remarkable
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The \(\pt\) distribution for the sub-leading photon (see
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resemblance to the \stone\ distribution for all other stages, although
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\cref{fig:disc-pT_subl}) shows remarkable resemblance to the \stone\
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there is a very minute bias to lower \(\pt\). This is consistent with
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distribution for all other stages, although there is a very minute
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the mechanism described above so that events that subtract (very small
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bias to lower \(\pt\). This is consistent with the mechanism described
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amounts of) \(\pt\) from the sub-leading second photon are more
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above so that events that subtract (very small amounts of) \(\pt\)
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common. Interestingly, the effects of primordial \(\pt\) not very
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from the sub-leading second photon are more common. Interestingly, the
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visible.
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effects of primordial \(\pt\) not very visible.
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The distribution for the invariant mass (see \cref{fig:disc-inv_m})
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In leading order, the phase space cuts impose a hard lower bound to
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shows that events with lower c.m.\ energies than the \stone\ threshold
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the invariant mass of the photon system. Parton showers can give
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can pass the cuts by being \(\pt\) boosted. The decline of the cross
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recoil momentum to the partons in such a way, that events with lower
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section towards lower energies is much steeper than the PDF-induced
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invariant mass pass the cuts. The distribution for the invariant mass
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decline towards higher energies. High \(\pt\) boost to \emph{both}
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(see \cref{fig:disc-inv_m}) shows that effect. The decline of the
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photons are very rare, which supports the reasoning about the drop in
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cross section towards lower energies is much steeper than the
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total cross section. The tendency for higher \(\pt\) boosts of the
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PDF-induced decline towards higher energies. High \(\pt\) boost to
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photon system in the \sttwo\ stage shows in a slight enhancement of
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\emph{both} photons are very rare (+ NLO suppressed), which supports
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the \sttwo\ cross section at low \(\pt > \gev{2}\).
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the reasoning about the drop in total cross section.
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The angular distributions of the leading photon in
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The angular distributions of the leading photon in
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\cref{fig:disc-cos_theta,fig:disc-eta} are most affected by the
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\cref{fig:disc-cos_theta,fig:disc-eta} are most affected by the
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@ -182,13 +192,15 @@ cross section distributions are similar in shape extends further. In
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the CS frame effects of the non-zero \(\pt\) of the photon system are
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the CS frame effects of the non-zero \(\pt\) of the photon system are
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(somewhat weakly) suppressed.
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(somewhat weakly) suppressed.
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It becomes clear, that the \sttwo\ and \stthree\ have the biggest
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It becomes clear, that parton showering and the primordial transverse
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effect on the shape of observables, as they affect kinematics
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momentum have the biggest effect on the shape of observables, as they
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directly. Isolation effects show most with the \stfour\ and especially
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affect the kinematics of the diphoton process directly. Isolation
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the \stfive\ stages. In angular observables hard process alone gives a
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effects show most through hadronization and especially multiple
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reasonably good qualitative picture, but in most other observables
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interactions. In observables that exist in leading order
|
||||||
non-LO effects introduce considerable deviations and have to be taken
|
(\(\eta, \pt\), \ldots), the hard process alone gives a reasonably
|
||||||
into account.
|
good qualitative picture, but in most other observables non-LO effects
|
||||||
|
introduce considerable deviations and have to be taken into account
|
||||||
|
for a realistic study. Even with this simple process.
|
||||||
|
|
||||||
%%% LOCAL Variables:
|
%%% LOCAL Variables:
|
||||||
%%% mode: latex
|
%%% mode: latex
|
||||||
|
|
|
@ -9,11 +9,11 @@ listed below.
|
||||||
%
|
%
|
||||||
\begin{description}
|
\begin{description}
|
||||||
\item[LO] The hard process on parton level as used in \cref{sec:pdf_results}.
|
\item[LO] The hard process on parton level as used in \cref{sec:pdf_results}.
|
||||||
\item[LO+PS] The shower generator of \sherpa, \emph{CSS}
|
\item[LO+PS] The shower generator of \sherpa,
|
||||||
(dipole-shower), is activated and simulates initial state
|
\emph{CSShower}~\cite{schumann2008:ap} (dipole-shower), is activated and
|
||||||
radiation. The recoil scheme proposed in~\cite{hoeche2009:ha}, which
|
simulates initial state radiation. The recoil scheme proposed
|
||||||
has been proven more accurate for diphoton production at leading
|
in~\cite{hoeche2009:ha}, which has been proven more accurate for
|
||||||
order, has been enabled.
|
diphoton production at leading order, has been enabled.
|
||||||
\item[LO+PS+pT] The beam remnants are simulated, giving rise to
|
\item[LO+PS+pT] The beam remnants are simulated, giving rise to
|
||||||
aditional radiation and parton showers. Also the partons are being
|
aditional radiation and parton showers. Also the partons are being
|
||||||
assigned primordial \(\pt\), distributed like a Gaussian with a mean
|
assigned primordial \(\pt\), distributed like a Gaussian with a mean
|
||||||
|
@ -21,13 +21,14 @@ listed below.
|
||||||
\SI{.8}{\giga\electronvolt}\footnote{Those values are \sherpa 's
|
\SI{.8}{\giga\electronvolt}\footnote{Those values are \sherpa 's
|
||||||
defaults.}.
|
defaults.}.
|
||||||
\item[LO+PS+pT+Hadronization] A cluster hadronization model
|
\item[LO+PS+pT+Hadronization] A cluster hadronization model
|
||||||
implemented in \emph{Ahadic} is activated. The shower particles are
|
implemented in \emph{Ahadic}~\cite{Winter2003:tt} is
|
||||||
being hadronized and the decay of the resulting hadrons simulated if
|
activated. The shower particles are being hadronized and the decay
|
||||||
they are unstable.
|
of the resulting hadrons simulated if they are unstable.
|
||||||
\item[LO+PS+pT+Hadronization+MI] Multiple Interactions (MI) based on
|
\item[LO+PS+pT+Hadronization+MI] Multiple Interactions (MI) based on
|
||||||
the Sj\"ostrand-van-Zijl Model are simulated. The MI are parton
|
the Sj\"ostrand-van-Zijl Model are simulated with
|
||||||
shower corrected, so that there are generally more particles in the
|
\emph{Amisic}~\cite{Bothmann:2019yzt}. The MI are parton shower
|
||||||
final state.
|
corrected, so that there are generally more particles in the final
|
||||||
|
state.
|
||||||
\end{description}
|
\end{description}
|
||||||
%
|
%
|
||||||
A detailed description of the implementation of those models can be
|
A detailed description of the implementation of those models can be
|
||||||
|
@ -39,7 +40,7 @@ configuration can be found in \cref{sec:ppruncardfull}. The
|
||||||
are the same as in \cref{sec:ppxs} and the beam energies have been
|
are the same as in \cref{sec:ppxs} and the beam energies have been
|
||||||
chosen as \SI{6500}{\giga\electronvolt} to resemble \lhc\ conditions.
|
chosen as \SI{6500}{\giga\electronvolt} to resemble \lhc\ conditions.
|
||||||
The cuts on the hard process have been loosened to
|
The cuts on the hard process have been loosened to
|
||||||
\(\pt \geq \SI{5}{\giga\electronvolt}\) and \(\abs{\eta}\leq 3\) to
|
\(\pt \geq \SI{5}{\giga\electronvolt}\) and \(\abs{\eta}\leq 3\)
|
||||||
because jets and primordial \(\pt\) can increase the final state
|
because jets and primordial \(\pt\) can increase the final state
|
||||||
\(\pt\) to fall into the analysis cuts.
|
\(\pt\) to fall into the analysis cuts.
|
||||||
|
|
||||||
|
@ -58,19 +59,16 @@ from hadron decays, the analysis only selects prompt photons with the
|
||||||
highest \(\pt\) (leading photons). Furthermore a cone of
|
highest \(\pt\) (leading photons). Furthermore a cone of
|
||||||
\[R = \sqrt{\qty(\Delta\varphi)^2 + \qty(\Delta\eta)^2} \leq 0.4\]
|
\[R = \sqrt{\qty(\Delta\varphi)^2 + \qty(\Delta\eta)^2} \leq 0.4\]
|
||||||
around each photon must not contain more than \SI{4.5}{\percent} of
|
around each photon must not contain more than \SI{4.5}{\percent} of
|
||||||
the photon transverse momentum (\(+ \SI{6}{\giga\electronvolt}\)),
|
the photon transverse momentum (\(+ \SI{6}{\giga\electronvolt}\)), to
|
||||||
attempting to exclude photons stemming from hadron decay are filtered
|
simulate experimental photon isolation. The leading photons are
|
||||||
out. The leading photons are required to have \(\Delta R > 0.45\), to
|
required to have \(\Delta R > 0.45\), to filter photons with
|
||||||
filter out colinear photons, as they likely stem from hadron
|
overlapping isolation cones, which would be hard to isolate in
|
||||||
decays.
|
experiments. In truth, the analysis already excludes such photons,
|
||||||
% TODO: only for experiments, do not overlap photon iso cones, einfach
|
but to be compatible with experimental data, which must rely on such
|
||||||
% weglassen
|
|
||||||
|
|
||||||
In truth, the analysis already excludes such photons, but to
|
|
||||||
be compatible with experimental data, which must rely on such
|
|
||||||
criteria, they have been included. These cuts are called
|
criteria, they have been included. These cuts are called
|
||||||
\emph{isolation cuts}. The code of the analysis is listed in
|
\emph{isolation cuts}. The code of the analysis is listed in
|
||||||
\cref{sec:ppanalysisfull}.
|
\cref{sec:ppanalysisfull} and has been adapted from code privately
|
||||||
|
communicated by Frank Siegert and Heberth Torres.
|
||||||
|
|
||||||
The production of photons in showers has not been considered.
|
The production of photons in showers has not been considered.
|
||||||
|
|
||||||
|
|
|
@ -262,3 +262,51 @@
|
||||||
location = {Austin, Texas},
|
location = {Austin, Texas},
|
||||||
series = {LLVM ’15}
|
series = {LLVM ’15}
|
||||||
}
|
}
|
||||||
|
|
||||||
|
@article{hoeche2009:ha,
|
||||||
|
author = {Hoeche, Stefan and Schumann, Steffen and Siegert,
|
||||||
|
Frank},
|
||||||
|
year = {2009},
|
||||||
|
month = {12},
|
||||||
|
pages = {},
|
||||||
|
title = {Hard photon production and matrix-element
|
||||||
|
parton-shower merging},
|
||||||
|
volume = {81},
|
||||||
|
journal = {Physical Review D},
|
||||||
|
doi = {10.1103/PhysRevD.81.034026}
|
||||||
|
}
|
||||||
|
|
||||||
|
@misc{porter2008:te,
|
||||||
|
title = {Testing Consistency of Two Histograms},
|
||||||
|
author = {Frank C. Porter},
|
||||||
|
year = {2008},
|
||||||
|
eprint = {0804.0380},
|
||||||
|
archivePrefix ={arXiv},
|
||||||
|
primaryClass = {physics.data-an}
|
||||||
|
}
|
||||||
|
|
||||||
|
@article{schumann2008:ap,
|
||||||
|
author = {Schumann, Steffen and Krauss, Frank},
|
||||||
|
year = {2008},
|
||||||
|
month = {03},
|
||||||
|
pages = {038},
|
||||||
|
title = {A parton shower algorithm based on Catani-Seymour
|
||||||
|
dipole factorisation},
|
||||||
|
volume = {2008},
|
||||||
|
journal = {Journal of High Energy Physics},
|
||||||
|
doi = {10.1088/1126-6708/2008/03/038}
|
||||||
|
}
|
||||||
|
|
||||||
|
@article{Winter2003:tt,
|
||||||
|
author = "Winter, Jan-Christopher and Krauss, Frank and Soff,
|
||||||
|
Gerhard",
|
||||||
|
title = "{A Modified cluster hadronization model}",
|
||||||
|
eprint = "hep-ph/0311085",
|
||||||
|
archivePrefix ="arXiv",
|
||||||
|
reportNumber = "CERN-TH-2003-272",
|
||||||
|
doi = "10.1140/epjc/s2004-01960-8",
|
||||||
|
journal = "Eur. Phys. J. C",
|
||||||
|
volume = "36",
|
||||||
|
pages = "381--395",
|
||||||
|
year = "2004"
|
||||||
|
}
|
||||||
|
|
57
notes.org
57
notes.org
|
@ -172,10 +172,13 @@ Viele Gruesse, Frank
|
||||||
** what does inclusive mean
|
** what does inclusive mean
|
||||||
** Normalize to XS
|
** Normalize to XS
|
||||||
** y axis label for normalized histos
|
** y axis label for normalized histos
|
||||||
** TODO PDF cannot be derived: in principle?
|
** DONE PDF cannot be derived: in principle?
|
||||||
** TODO still compatible?
|
** DONE still compatible?
|
||||||
** TODO cite atlas paper (analysis?)
|
** DONE cite atlas paper (analysis?)
|
||||||
** TODO call it distribution?
|
** DONE call it distribution?
|
||||||
|
** DONE diphoton caps?
|
||||||
|
** DONE do remnants radiate?
|
||||||
|
** TODO ask about nlo emissions
|
||||||
* Work Log
|
* Work Log
|
||||||
** 18.03
|
** 18.03
|
||||||
- habe mich in manche konzeptionelle Dinge ziemlich verrannt!
|
- habe mich in manche konzeptionelle Dinge ziemlich verrannt!
|
||||||
|
@ -183,12 +186,13 @@ Viele Gruesse, Frank
|
||||||
* Todo
|
* Todo
|
||||||
** TODO lab xs kuerzen
|
** TODO lab xs kuerzen
|
||||||
** TODO shower scale anpassen
|
** TODO shower scale anpassen
|
||||||
** TODO effekt shower und kperp
|
** DONE effekt shower und kperp
|
||||||
** DONE y-axis a.u.!
|
** DONE y-axis a.u.!
|
||||||
** DONE mean, var einzeichnen
|
** DONE mean, var einzeichnen
|
||||||
** DONE Variance of vegas weighted f!
|
** DONE Variance of vegas weighted f!
|
||||||
** DONE look at xs plot -> they seem different
|
** DONE look at xs plot -> they seem different
|
||||||
** DONE take new sample: still bias?
|
** DONE take new sample: still bias?
|
||||||
|
** DONE umnumerieren
|
||||||
|
|
||||||
* Observations
|
* Observations
|
||||||
** XS
|
** XS
|
||||||
|
@ -264,3 +268,46 @@ Viele Gruesse, Frank
|
||||||
- biggest effect is the jet kick, photons are no qcd particles and
|
- biggest effect is the jet kick, photons are no qcd particles and
|
||||||
not touched after hard process
|
not touched after hard process
|
||||||
- no em radiation activated: would add more noise, here no additional photons
|
- no em radiation activated: would add more noise, here no additional photons
|
||||||
|
|
||||||
|
|
||||||
|
426 .. ref for CSS
|
||||||
|
433/436 .. refs
|
||||||
|
443 .. to zu viel
|
||||||
|
448 .. azimuthal
|
||||||
|
451 .. verb zu viel
|
||||||
|
452 .. collinear
|
||||||
|
|
||||||
|
kick -> recoil, klarer, momentum conservation am anfang! 481/6708
|
||||||
|
|
||||||
|
primordial pT, erklaeren fermi motion
|
||||||
|
|
||||||
|
figs umsortieren
|
||||||
|
|
||||||
|
484 .. often
|
||||||
|
off the orderd -> of
|
||||||
|
|
||||||
|
ok .. pT > 1e-1 MI schwer zu sagen, uninteressant, weglassen, nicht messbar
|
||||||
|
|
||||||
|
discuss -> parton shower collinear limes naeherung
|
||||||
|
(falling off steeply), kein grosses pT, keine gute naeherung in > 10 GeV
|
||||||
|
|
||||||
|
|
||||||
|
nontrivial feater of .. modeling
|
||||||
|
|
||||||
|
|
||||||
|
492 .. back to back preference -> nur folge der nlo unterdrueck
|
||||||
|
|
||||||
|
was ist LO threshhold, durch pT cuts
|
||||||
|
ist keine c.m. energy -> inv mass
|
||||||
|
|
||||||
|
very rare -> higher order (α_s kleiner) harte qcd kosten!
|
||||||
|
|
||||||
|
inv m LO+PS nicht verschieben 510 .. 511
|
||||||
|
|
||||||
|
524 .. welcher effekt
|
||||||
|
|
||||||
|
bigger picture .. lo bild -> geeignet, auch einfache betroffen (auch am anfang) uberall auswirkung
|
||||||
|
|
||||||
|
outlook very simple, nlo ME verwenden, fragmentation aus parton (dijet), neue photon iso + viel mehr
|
||||||
|
|
||||||
|
chi^2 test
|
||||||
|
|
|
@ -10,7 +10,7 @@ Beams: [2212, 2212]
|
||||||
Energies: [6500, 6500]
|
Energies: [6500, 6500]
|
||||||
#Luminosity_fb: 139.0
|
#Luminosity_fb: 139.0
|
||||||
Description:
|
Description:
|
||||||
'An analysis used to compare different configuration of the Sherpa event generator.'
|
'An analysis used to compare different configurations of the Sherpa event generator.'
|
||||||
ValidationInfo:
|
ValidationInfo:
|
||||||
'Not validated'
|
'Not validated'
|
||||||
#ReleaseTests:
|
#ReleaseTests:
|
||||||
|
|
|
@ -29,7 +29,7 @@ Title=$m_{\gamma\gamma}$ of the two leading photons
|
||||||
XLabel=$m_{\gamma\gamma}$ [GeV]
|
XLabel=$m_{\gamma\gamma}$ [GeV]
|
||||||
YLabel=$\mathrm{d}\sigma/\mathrm{d}m_{\gamma\gamma}$ [pb GeV$^{-1}$]
|
YLabel=$\mathrm{d}\sigma/\mathrm{d}m_{\gamma\gamma}$ [pb GeV$^{-1}$]
|
||||||
LogX=1
|
LogX=1
|
||||||
XMin=1
|
XMin=10.5
|
||||||
XMax=2000
|
XMax=2000
|
||||||
# END PLOT
|
# END PLOT
|
||||||
|
|
||||||
|
@ -73,6 +73,7 @@ XLabel=$\pT$
|
||||||
YLabel=$\mathrm{d}\sigma/\mathrm{d}\pT_{\gamma\gamma}$ [pb GeV$^{-1}$]
|
YLabel=$\mathrm{d}\sigma/\mathrm{d}\pT_{\gamma\gamma}$ [pb GeV$^{-1}$]
|
||||||
LogY=1
|
LogY=1
|
||||||
LogX=1
|
LogX=1
|
||||||
|
XMin=1e-1
|
||||||
# END PLOT
|
# END PLOT
|
||||||
|
|
||||||
# BEGIN PLOT /MC_DIPHOTON_PROTON/xs
|
# BEGIN PLOT /MC_DIPHOTON_PROTON/xs
|
||||||
|
|
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Loading…
Add table
Reference in a new issue