################################################################################ # # Copyright (c) 2009 The MadGraph5_aMC@NLO Development team and Contributors # # This file is a part of the MadGraph5_aMC@NLO project, an application which # automatically generates Feynman diagrams and matrix elements for arbitrary # high-energy processes in the Standard Model and beyond. # # It is subject to the MadGraph5_aMC@NLO license which should accompany this # distribution. # # For more information, visit madgraph.phys.ucl.ac.be and amcatnlo.web.cern.ch # ################################################################################ tutorial_aMCatNLO = """ You have entered tutorial mode. This will introduce you to the main syntax options of MadGraph5_aMC@NLO for the computation of processes involving NLO corrections. To learn more about the different options for a command, you can use MG_aMC>help A_CMD To see a list of all commands, use MG_aMC>help The goal of this tutorial is to learn how to generate a process and to produce an output for MadGraph5_aMC@NLO. In this part we will learn a) How to generate a process involving NLO corrections b) How to create the corresponding output for MadGraph5_aMC@NLO c) How to run this output for computing NLO corrections If you have FastJet (v3 or later) installed on your computer and you wish to link it, please update the mg5_configuration file or type MG5_aMC>set fastjet /path/to/fastjet-config Otherwise the basic fastjet functionalities included in FJcore (shipped with MadGraph5_aMC@NLO) will be used. Let's start with the first point, how to generate a process at NLO: MG5_aMC>generate p p > e+ ve [QCD] Note that a space is mandatory between the particle names and that '[QCD]' specifies that you want to consider QCD NLO corrections. Couplings different than QCD cannot be perturbed yet. """ tutorial = tutorial_aMCatNLO generate = """ You have just generated a new process. You can find more information on supported syntax by using: MG_aMC>help generate To list all defined processes, type MG_aMC>display processes If you want to know more about particles and multiparticles present, write MG_aMC>display particles MG_aMC>display multiparticles If you want to add a second process, use the add process command: MG_aMC>add process p p > e+ e- [QCD] @2 At this stage you can export your processes. This is done simply by typing: MG_aMC>output MY_FIRST_AMCATNLO_RUN """ display_processes = """ You have seen a list of the already defined processes. At this stage you can export your processes to different formats. In this tutorial, we will explain how to create a valid output for MadGraph5_aMC@NLO. This is done simply by typing: MG_aMC>output MY_FIRST_AMCTANLO_RUN """ add_process = """ You have added a process to your process list. At this stage you can export your processes. This is done simply by typing: MG_aMC>output MY_FIRST_AMCATNLO_RUN """ output = """ If you are following the tutorial, a directory MY_FIRST_AMCATNLO_RUN has been created which can be used in order to run simulation including NLO corrections. Additionally to the commands in the bin directory (see MY_FIRST_AMCATNLO_RUN/README), you can also generate your events/compute the cross-section from this interface. You will generate events to be showered a la MC@NLO, compute the theoretical and PDF error on the fly (if asked for in the run_card.dat) and shower the events with the parton_shower MonteCarlo specified in the run_card.dat, generating a file in the StdHEP format. Please note that, since shower-specific counterterms have to be included in the calculation, the parton level sample you will obtain can only be showered with the selected MonteCarlo. Note also that, because of the way they have been generated, the parton-level events in the .lhe file are UNPHYSICAL. In order to obtain physical results, please use the .hep file Please enter MG_aMC> launch If you just want to generate the parton level .lhe file, please enter MG_aMC> launch -p (you can interrupt the computation to continue the tutorial by pressing Ctrl-C) At any time, you can access more commands/options for running the output by switching to an interactive interface for a given output folder 'MyFolder'. You can do so by typing: MG_aMC> launch -i MyFolder Please see MY_FIRST_AMCATNLO_RUN/README to know about the available commands. To know the possible options/modes for each command, simply tiple 'MyFolder'> help COMMAND from the interface bound to the 'MyFolder' output. """ open_index = output launch = """This step ends the tutorial of the basic commands of for running processes including NLO corrections. You can always use the help to see the options available for different commands. For example, if you want to know how to launch on multicore/cluster just type MG_aMC>help launch To learn more about MadLoop StandAlone checks and runs, you can now follow its tutorial with: MG_aMC>tutorial MadLoop To simply close this tutorial, enter MG_aMC>tutorial stop If you want to exit MG5, enter MG_aMC>exit """