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\topheading{Input file configuration}
\midheading{Run-time input file parameters}
MCFM execution is performed in the {\tt Bin/} directory,
with syntax:
\begin{center}
{\tt mcfm }{\it input.ini}
\end{center}
If no command line options are given, then MCFM will default
to using the file {\tt input.ini} in the current directory for
choosing options. The \texttt{input.ini} file can be in any directory and
then the first argument to \texttt{mcfm} should be the location
of the file. Furthermore, one can overwrite or append single
configuration options with additional parameters like:
\begin{center}
\texttt{./mcfm benchmark/input.ini -general\%part=nlo -lhapdf\%dopdferrors=.true.}
\end{center}
Here specifying a parameter uses a single dash, then the section name as in the input file (see below), followed
by a percent sign, followed by the option name, followed by an equal sign and the actual value of the setting.
All default settings in the input file are explained below, as well as further optional parameters.
The top level setting \texttt{mcfm\_version} specifies the input file version number and it must match the version of
the code being used.
The general structure of a fixed-order calculation up to NNLO is as follows:
\begin{equation}
\sigma = \sigma_0 + \Delta\sigma_1 + \Delta\sigma_2 \,,
\end{equation}
where $\Delta\sigma_k$ is of order $\alpha_s^k$ with respect to the leading
order cross section $\sigma_0$, thus representing the
N$^k$LO contribution to the cross section.
When performing the NLO calculation using dipole subtraction
its contribution to the cross section can be decomposed as,
\begin{equation}
\Delta\sigma_1 = \Delta\sigma_1^v + \Delta\sigma_1^r \,.
\end{equation}
$\Delta\sigma_1^v$ includes virtual (loop) contributions, as well
as counterterms that render them finite.
$\Delta\sigma_1^r$ includes contributions from diagrams
involving real parton emission, again with counterterms to make them finite.
Only the sum of $\Delta\sigma_1^v$ and $\Delta\sigma_1^v$ is physical.
This contribution can also be computed using a slicing method with the
corresponding decomposition,
\begin{equation}
\Delta\sigma_1^a = \Delta\sigma_1^{a,<} + \Delta\sigma_1^{a, >} \,.
\end{equation}
$a$ labels the slicing resolution variable, which in MCFM can be either
0-jettiness, $q_T$ (of a color-singlet system) or $p_T^{j_1}$ (lead jet $p_T$)
(thus corresponding to a jet veto).
$\Delta\sigma_1^{a,<}$ is termed the below-cut slicing contribution which is
computed by the means of a factorization theorem and includes loop contributions.
$\Delta\sigma_1^{a,>}$ is the above-cut contribution containing radiation of
an additional parton.
Only the sum $\Delta\sigma_1^a$ is physical and contains a dependence on
the slicing resolution variable $a_{\text{cut}}$ that tends to zero as
$a_{\text{cut}} \to 0$
At NNLO only slicing calculations are available. The decomposition is,
\begin{equation}
\Delta\sigma_2^a = \Delta\sigma_2^{a,<} + \Delta\sigma_2^{a, v>} + \Delta\sigma_2^{a, r>} \,.
\end{equation}
$\Delta\sigma_2^{a,<}$ is the below-cut slicing contribution containing 2-loop
contributions.
$\Delta\sigma_1^{a, v>}$ is the above-cut contribution containing loop corrections
to radiation of an additional parton.
$\Delta\sigma_1^{a, r>}$ is the above-cut contribution representing
radiation of up to two additional partons.
Only the sum $\Delta\sigma_2^a$ is physical and contains a dependence on
the slicing resolution variable $a_{\text{cut}}$ that tends to zero as
$a_{\text{cut}} \to 0$
The type of computation that is performed depends on the parameter
\texttt{part} in the \texttt{general} section.
The list of possible values,
and the associated meaning, is shown in Tables~\ref{tab:partchoicesfo}
and~\ref{tab:partchoicesresum}. They can also be listed by
setting \texttt{part} equal to \texttt{help in the input file}.
\begin{longtable}{p{4.5cm}p{9.0cm}}
\caption{Possible values for the parameter \texttt{part} that correspond to
performing a fixed-order calculation. \label{tab:partchoicesfo}} \\
\hline
\texttt{part} & description\\
\hline
{\tt lo}/{\tt lord} &
$\sigma_0$
\\
{\tt virt} &
$\Delta\sigma_1^v$
\\
{\tt real} &
$\Delta\sigma_1^r$
\\
{\tt nlocoeff}/{\tt totacoeff} &
$\Delta\sigma_1$
\\
{\tt nlo}/{\tt tota} &
$\sigma_0+\Delta\sigma_1$. For photon processes that include fragmentation,
{\tt nlo} also includes the calculation of the fragmentation ({\tt frag})
contributions.
\\
{\tt frag} &
Processes 280, 285, 290, 295, 300-302, 305-307, 820-823 only, see sections~\ref{subsec:gamgam},
\ref{subsec:wgamma} and
\ref{subsec:zgamma} below.
\\
{\tt nlodk}/{\tt todk} &
Processes 114, 161, 166, 171, 176, 181, 186, 141, 146, 149, 233, 238, 501, 511 only, see
sections~\ref{subsec:stop} and
\ref{subsec:wt} below.
\\
{\tt snloR} & $\Delta\sigma_1^{a,>}$
\\
{\tt snloV} & $\Delta\sigma_1^{a,<}$
\\
{\tt snlocoeff}/{\tt scetnlocoeff} & $\Delta\sigma_1^a$
\\
{\tt snlo}/{\tt scetnlo} & $\sigma_0 + \Delta\sigma_1^a$
\\
{\tt nnloVVcoeff} & $\Delta\sigma_2^{a,<}$
\\
{\tt nnloRVcoeff} & $\Delta\sigma_2^{a,v>}$
\\
{\tt nnloRRcoeff} & $\Delta\sigma_2^{a,r>}$
\\
{\tt nnloVV} & $\Delta\sigma_1^{a,<} + \Delta\sigma_2^{a,<}$
\\
{\tt nnloRV} & $\Delta\sigma_1^{a,>} + \Delta\sigma_2^{a,v>}$
\\
{\tt nnloRR} & $\Delta\sigma_2^{a,r>}$
\\
{\tt nnlocoeff} & $\Delta\sigma_2^{a}$
\\
{\tt nnlo} & $\sigma_0 + \Delta\sigma_1 + \Delta\sigma_2^{a}$
\end{longtable}
\begin{longtable}{p{4.5cm}p{9.0cm}}
\caption{Possible values for the parameter \texttt{part} that correspond to
performing a calculation including large-log resummation. \label{tab:partchoicesresum}} \\
\hline
\texttt{part} & description\\
\hline
{\tt resLO} & NLL resummed and matched
\\
{\tt resonlyLO} & NLL resummed only
\\
{\tt resonlyLOp} & NLLp resummed only
\\
{\tt resexpNLO} & NNLL resummed expanded to NLO
\\
{\tt resonlyNLO} & NNLL resummed
\\
{\tt resaboveNLO} & fixed-order matching to NLO
\\
{\tt resmatchcorrNLO} & matching corrections at NLO
\\
{\tt resonlyNLOp} & NNLLp resummed
\\
{\tt resexpNNLO} & N$^3$LL resummed expanded to NNLO
\\
{\tt resonlyNNLO} & N$^3$LL resummed
\\
{\tt resaboveNNLO} & fixed-order matching to NLO
\\
{\tt resmatchcorrNNLO} & matching corrections at NLO
\\
{\tt resLOp} & NLLp resummed and matched
\\
{\tt resNLO} & NNLL resummed, matched to NLO
\\
{\tt resNLOp} & N$^3$LL resummed, matched to NLO
\\
{\tt resNNLO} & N$^3$LL resummed, matched to NNLO
\\
{\tt resNNLOp} & N$^3$LLp resummed, matched to NNLO
\\
{\tt resonlyNNLOp} & N$^3$LLp resummed
\end{longtable}
\bottomheading{General}
\input{sections/table_general.tex}
\bottomheading{Resummation}
\input{sections/table_resummation.tex}
\bottomheading{NNLO}
\input{sections/table_nnlo.tex}
\bottomheading{PDFs}
\input{sections/table_pdf.tex}
\bottomheading{LHAPDF}
\input{sections/table_lhapdf.tex}
\bottomheading{Scales}
\input{sections/table_scales.tex}
\begin{table}
\begin{center}
\begin{longtable}{|l|l|l|}
\hline
{\tt dynamic scale} & $\mu_0^2$ & comments\\
\hline
{\tt m(34)} & $(p_3+p_4)^2$ & \\
{\tt m(345)} & $(p_3+p_4+p_5)^2$ & \\
{\tt m(3456)} & $(p_3+p_4+p_5+p_6)^2$ & \\
{\tt sqrt(M\pow 2+pt34\pow 2)} & $M^2 + (\vec{p_T}_3 + \vec{p_T}_4)^2$ & $M=$~mass of particle 3+4 \\
{\tt sqrt(M\pow 2+pt345\pow 2)} & $M^2 + (\vec{p_T}_3 + \vec{p_T}_4 + \vec{p_T}_5)^2$ & $M=$~mass of
particle 3+4+5 \\
{\tt sqrt(M\pow 2+pt5\pow 2)} & $M^2 + \vec{p_T}_5^2$ & $M=$~mass of particle 3+4 \\
{\tt sqrt(M\pow 2+ptj1\pow 2)} & $M^2 + \vec{p_T}_{j_1}^2$ & $M=$~mass(3+4), $j_1=$ leading $p_T$ jet \\
{\tt pt(photon)} & $\vec{p_T}_\gamma^2$ & \\
{\tt pt(j1)} & $\vec{p_T}_{j_1}^2$ & \\
{\tt HT} & $\sum_{i=1}^n {p_T}_i$ & $n$ particles (partons, not jets) \\
\hline
\hline\end{longtable}
\end{center}
\caption{Choices of the input parameter {\tt dynamicscale} that result in an event-by-event
calculation of all relevant scales using the given reference scale-squared $\mu_0^2$.
\label{tab:dynamicscales}}
\end{table}
\bottomheading{Masses}
\input{sections/table_masses.tex}
\bottomheading{Basic jets}
\label{basicjets}
\input{sections/table_basicjets.tex}
\bottomheading{Mass cuts}
\label{masscuts}
\input{sections/table_masscuts.tex}
\bottomheading{Cuts}
\input{sections/table_cuts1.tex}
\bottomheading{Cuts (continued)}
\input{sections/table_cuts2.tex}
\bottomheading{Photon}
\input{sections/table_photon.tex}
\bottomheading{Histograms}
\input{sections/table_histogram.tex}
\bottomheading{Imtegration}
\input{sections/table_integration.tex}
\midheading{Process specific options}
\bottomheading{Single Top}
\input{sections/table_singletop.tex}
\bottomheading{Anomalous $W/Z$ couplings}
\input{sections/table_anom_wz.tex}
\bottomheading{$W/Z$+2 jets}
\input{sections/table_wz2jet.tex}
\bottomheading{H jetmass}
\input{sections/table_hjetmass.tex}
\bottomheading{Anomalous $H$ couplings}
\input{sections/table_anom_higgs.tex}
\bottomheading{Extra}
\input{sections/table_extra.tex}
\bottomheading{Dipoles}
\input{sections/table_dipoles.tex}