Florian Bonnet

Introduction to MadGraph/MadEvent:

Florian Bonnet

January 21st 2011

INFN - Sezione di Padova

an informal tutorial

What I will do

Why using MadGraph/MadEvent (MG/ME) Getting familiar with the MG/ME environment One example from A to Z Introduction to model building

What I will not do

Discuss the physics inside the program Discuss technical details (compilers ...)

http://madgraph.roma2.infn.ithttp://madgraph.hep.uiucc.eduhttp://madgraph.phys.ucl.ac.be

F. Bonnet MadGraph/MadEvent 21/01/2011

http://madgraph.roma2.infn.it


http://madgrpah.hep.uiucc.edu


http://madgrpah.phys.ucl.ac.be


Making discoveries at the LHC

Finding excesses over the SM backgrounds

need to be well measured from data

need to be well described by MC

Use the peculiar features of signals (mass distributions, kinematics, angular distributions...) to:

Improve signal/background ratio Identify the quantum numbers of new particles


Making discoveries at the LHC

Finding excesses over the SM backgrounds

need to be well measured from data


Use the peculiar features of signals (mass distributions, kinematics, angular distributions...) to:

Improve signal/background ratio Identify the quantum numbers of new particles



Why MadGraph/MadEvent ?

Idea : a MC code for theorists to talk to experimentalists

A huge amount of BSM models Data

?





?

Lagrangian

Automatized Feynman Rules

Signal & Background Events (parton level)

Parton shower & hadronization

Detector simulation





?

Lagrangian

Automatized Feynman Rules

Signal & Background Events (parton level)

Parton shower & hadronization

Detector simulation

MadGraph

MadEvent

PYHTIA

PGS


MadGraph/MadEvent

On-line web interface Install whole package on your computer

Two ways to run MG/ME:

Let’s go to MG/ME directory!


MadGraph/MadEvent

MG/ME directory: Core

Basis of avalaible models

PYTHIA & PGS

Analysis ToolPlots

Working Module


MadGraph/MadEvent

Template directory:

Core

Storage of events

Core CoreCore

Binaries

Inputs


Cards directory:

proc_card.dat param_card.dat run_card.dat pythia_card.dat pgs_card.dat

processesmodel parametersrunning parametersPYTHIA optionsDetector charateristics

MadGraph/MadEvent


MadGraph/MadEvent

proc_card.dat param_card.dat run_card.dat pythia_card.dat pgs_card.dat

MadGraph MadEvent PYTHIA PGS

Feyn. diagramsAmplitudes Parton-level events Hadron-level

eventsDetector-level

events


Example

Signal: pp > h > mu+ e- ve~ vmg

g

Background: pp > w+w- > mu+ e- ve~ vm/h


Example

proc_card.dat

process ID


Example

proc_card.dat

highest order in couplings


Example

proc_card.dat model


Example

proc_card.dat


Example

./bin/newprocess.........

gunzip madevent.tar.gztar -xvf madevent.tar

Source code for the processes


Example

param_card.dat !parameters are not

independant: USE A CALCULATOR

Used by PYTHIA,Needed for any new

particle,you can use BRIDGEhttp://lepp.cornell.edu/public/theory/BRIDGE/index.html


http://lepp.cornell.edu/public/theory/BRIDGE/index.html




Example

run_card.dat

+ PRIMARY CUTS


Example

./bin/survey./bin/refine

Calculating cross-sections:

./bin/generate_events Generating events:

XXX_unweighted_events.lhe XXX_pythia_events.lhe XXX_pgs_events.lhco


Example

Analysis: MadAnalysis (simpler) or ROOT (more complete)


Example

Analysis: MadAnalysis (simpler)

Define classes of particles using PDG code

ma_card.dat


Example


Define cuts on events

ma_card.dat


Example


Define plots

ma_card.dat


Example


./plot_events

plots.top

signalbackground


Model building

Model =

Particles

Interactions

Couplings


Model building

Model =

Particles

Interactions

Couplings

particles.dat

interactions.dat

couplings.f

MadGraph


Model building

Model directory:

usrmod: old version usrmodFR: new version,


Model building

Model directory:

usrmod: old version

compatible with FeynRules

Mathematica package

Lagrangian FeynRulesparticles.datinteractions.datcouplings.f

Madgraph

usrmodFR: new version,

FeynRules

usrmodFR

FeynRulesmodel

modify cards usrmodFR new

model MadGraph

(feynrules.phys.ulc.ac.be)


Model building

Copy sm_FR directory and rename it NewModel


Model building

python2.5 ../usrmod_FR/usrmod.py save


Model building

Model =

Particles

Interactions

Couplings

particles.dat

interactions.dat

couplings.f

MadGraph


Model building

particles.dat

interactions.dat

couplings.f

name


Model building

particles.dat

interactions.dat

couplings.f

Fermion, Scalar, Vector ...


Model building

particles.dat

interactions.dat

couplings.f

Type of line in Feynman diagram


Model building

particles.dat

interactions.dat

couplings.f

Mass


Model building

particles.dat

interactions.dat

couplings.f

Width


Model building

particles.dat

interactions.dat

couplings.f

Color charge


Model building

particles.dat

interactions.dat

couplings.f

Name in Feynman diagram


Model building

particles.dat

interactions.dat

couplings.f

PDG code


Model building

particles.dat

interactions.dat

couplings.f

Majorana particles non existing code


Model building

particles.dat

interactions.dat

couplings.f

order: see HELAS libraries!Murayama et al., KEK-91-11, 1992


Model building

particles.dat

interactions.dat

couplings.f

name of coupling


Model building

particles.dat

interactions.dat

couplings.f

type of coupling


Model building

particles.dat

interactions.dat

couplings.f


Model building

python2.5 ../usrmod_FR/usrmod.py create


Model building

particles.dat

interactions.dat

couplings.f

GWEN(1)*PL + GWEN(2)*PR


Model building

particles.dat

interactions.dat

couplings.f


Model building

particles.dat

interactions.dat

couplings.f

input.incintparam_definition.inc

internal param.


Model building

particles.dat

interactions.dat

couplings.f


internal param.

ident_card.datparam_card.dat external param.


Model building

make testprog./testprog


Model building

Model =

Particles

Interactions

Couplings

particles.dat

interactions.dat

couplings.f

ident_card.datparam_card.dat


external param.

internal param.

MadGraph


Model building

FeynRules(feynrules.phys.ulc.ac.be)


Model building

Open and go into SM


Model building

Definition of model Output interface


Model building

SM.fr Indices Gauge Indices External Parameters Internal Parameters Gauge Groups Particles Lagrangian

param_card.dat


Model building


Internal parameters to write Lagrangian


Model building


particles.dat


Model building

SM.fr Indices Gauge Indices External Parameters Internal Parameters Gauge Groups Particles Lagrangian couplings.f

Let’s do a new model !


Model building

TypeI.fr

SM Type I


Model building

TypeI.fr

SM Type I

SM parametersSM parameters

+Type I new parameters


Model building

TypeI.fr

SM Type I


Model building

TypeI.fr

SM Type I

in the param_card.dat


Model building

TypeI.fr

SM Type I

Name of block in the param_card.dat


Model building

TypeI.fr

SM Type I

Default value


Model building

TypeI.fr

SM Type I

Ordering


Model building

TypeI.fr

SM Type I


Model building

TypeI.fr

SM Type I

Intermediate parameters to help

writing the Lagrangian

Mathematica -> Matrices allowed


Model building

TypeI.fr

SM Type I


Model building

TypeI.fr

SM Type I

Intermediate parameters to help

writing the Lagrangian


Model building

TypeI.fr

SM Type I


Model building

TypeI.fr

SM Type I

Kinetic terms

Vector in flavor space


Model building

TypeI.fr

SM Type I

Kinetic terms

Gamma Matrices


Model building

TypeI.fr

SM Type I

Kinetic terms

Partial derivative


Model building

TypeI.fr

SM Type I

Kinetic terms Kinetic terms


Model building

TypeI.fr

SM Type I

Gauge Interactions Gauge Interactions


Model building

TypeI.fr

SM Type I

Gauge Interactions Gauge Interactions


Model building

TypeI.fr

SM Type I

Yukawa Interactions Yukawa Interactions


Model building

TypeI.nb


Model building

TypeI.nb

TypeI


Model building

TypeI.nb


Model building

TypeI.nb

TypeI.fr


Model building

TypeI.nb


MadGraph 5


FeynRules MadGraph4 MadEvent PYTHIA PGS

MadGraph5

MadGraph 5


New features: New diagram generation (faster) New color structures Unlimited decay chains Compatible with PYTHIA 8 Automatic generation of HELAS routines

UFOUniversal FeynRules Output

ALOHAAutomatic Language-independent

Output of Helicity Ampltudes

self-contained Python code not tied to any matrix element generator

Automatic generation of the necessary HELAS code for any new model

Vertices with any Lorentz structure Effective vertices with any # particles

What I didn’t have time to talk about

ROOT (Tree & leaves, ExRootAnalysis etc) DELPHES (alternative to PGS) BRIDGE (Tool to calculte BR and width)


Summary

User-friendly MC: from Lagrangian to events Every level of simulation: cross-sections, parton-level, hadron-

level, detector level Compatible with FeynRules MadGraph 5 very exciting for BSM phenomenology.

If you have any question I’m in office 313, otherwise:

http://madgraph.roma2.infn.ithttp://madgraph.hep.uiucc.eduhttp://madgraph.phys.ucl.ac.befeynrules.phys.ulc.ab.be








Florian Bonnet

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