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18 lines
1.2 KiB
18 lines
1.2 KiB
\midheading{$Z\gamma\gamma j$ and $Z\gamma j j $, 303, 304, 308 and 309}
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These processes are available at LO only. The $Z/\gamma^*$ subsequently decays into
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either an $e^+ e^-$ pair ({\tt nproc=303,304}) or neutrinos ({\tt nproc=308,309}).
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Since these processes include a real photon and a jet, the cross section diverges
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when a photon or a jet is very soft or in the direction of the beam.
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Thus in order to produce sensible results, the input file must supply values for both
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{\tt gammptmin} and {\tt gammrapmax}, and {\tt ptjetmin} and {\tt etajetmax}.
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Moreover, when the parameters {\tt zerowidth}
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and {\tt removebr} are set to {\tt .false.} the decay $Z \to e^- e^+$ ({\tt nproc=303, 304})
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will include photon radiation from both leptons, so that a non-zero $R(\gamma,\ell)_{min}$
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({\tt Rgalmin})
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should also be supplied. This will ensure that the cross section is well-defined.
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Anomalous couplings are not currently implemented for these processes.
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%Processes {\tt 303} and {\tt 308} represents the production of a $Z$ boson (or virtual photon)
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%in association with a two photons and and an additional jet. These processes are available at leading order only.
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%These processes do not currently have anomalous couplings implemented.
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