The VISION of MadGraph and FeynRules Johan Alwall Fermilab MadGraph Spring 2011, Fermilab, May 3, 2011 Johan Alwall - The Vision of MG/FR 1
The LHC is on track! but where are we heading...? Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 2
What will be needed for the LHC? Automatic Exp - TH Very exotic communication NLO models Effective theories Exotic models Advanced Decay chains Matrix analysis techniques Elements Multi-jet samples Cluster/Grid Efficient Modelbuilding computing Automatic scans over model space Testing/robustness Decay Packages User friendliness Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 3
The Beginnings Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 4
The Beginnings Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 5
The Beginnings Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 6
First “offical” BSM Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 7
The Web Generation Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 8
Tools and BSM functionality arXiv:1007.3300 arXiv:0809.2410 arXiv:0805.2554 arXiv:0712.2770 arXiv:1010.4255 See talk by Kentarou Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 9
Speed arXiv:0908.4403 arXiv:1010.0748 arXiv:0909.5257 See talks by Junichi and Yoshitaro Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 10
Next-to-leading Order arXiv:1004.2905 arXiv:0908.4272 arXiv:1103.0621 See talk by Valentin + Automatic MC@NLO (to be presented by Paolo) + Automatic SUSY@NLO (see talk by MadGOLEM team) arXiv:1004.2905 Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 11
MadGraph ● MadGraph has evolved from pure matrix element generator to a multi-purpose platform for a large number of automatized tools ● Very strong trademark – very powerful tool ● However, inherent limitations and rigid output structure still place a limit on user friendliness and development possibilities ● Many developments have been veritable “tour- de-force” efforts with massive post-processing Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 12
FeynRules arXiv:0806.4194 Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 13
FeynRules arXiv:0806.4194 Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 14
FeynRules Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 15
FeynRules ● Easy-to-use but powerful Mathematica package – Generation of Feynman rules from any Lagrangean – Output of generator specific files using multiple generator translation interfaces – Continuous new improvements and developments See talk by FeynRules team ● However – output limited by the capabilities of the target generator in terms of Lorentz/color structures, multiparticle vertices, effective vertices etc. – e.g., implemented HELAS routines Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 16
Vision (anno 2008/9) ● Using FeynRules as a cornerstone, allows for unprecedented validation and testing of models, and efficient communication between theorists and experimentalists at any point in the simulation chain arXiv:0906.2474 Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 17
Replace this... TH PHENO EXP Idea Lagrangian Feyn. rules Aut. Feyn. rules Amplitudes Any amplitude 2→2 Amps Xsecs Any xsec New MC Signature Events Pythia+PGS Pythia New pythia More signatures Detector simulation Paper Paper Paper Data Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 18
… by this! TH EXP Idea Lagrangian FeynRules FeynRules Experimentalist ME generator Theorist Signatures Events Pythia PGS Detector simulation Data Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 19
… by this! TH EXP Idea Lagrangian FeynRules FeynRules Experimentalist ME generator Theorist Signatures Events Communication Pythia possible at any level – PGS Detector simulation optimal flexibility for all involved Data Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 20
… by this! TH EXP Idea Lagrangian FeynRules FeynRules Experimentalist ME generator Theorist Signatures Events (and of course, papers Pythia can be written at any PGS Detector simulation level as well) Data Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 21
Since then, we've raised the bar! ● Development of MadGraph 5 started in November 2009 ● Explicit goal – remove all limitations on old MadGraph – Speed – Number of particles – Types of interactions – Output languages and formats – Flexibility and modularity ● Did we succeed? Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 22
Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 23
Speed Matrix Element generation: + Ongoing work with recursion Matrix Element for multiparton evaluation calculations in (Fortran): MG5, see talk by Yoshitaro Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 24
Number of particles Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 25
Types of interactions Higgs Effective Theory Multi-fermion vertices Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 26
Types of interactions Comparisons between explicit propagators and 4-fermion vertex t-channel u u > t t s-channel u u > t t Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 27
Types of interactions Color sextet and ε ijk implementations 7 TeV LHC Jet p T :s, fully matched Diquark cross sections with coupling 0.01 pp → D + 0,1,2 jets Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 28
Output languages and formats Pythia 8 C++ output #include "SigmaProcess.h" #include "Parameters_sm.h" using namespace std; namespace Pythia8 { //========================================== // A class for calculating the matrix elements for // Process: u u~ > t t~ QED=0 @1 // Process: c c~ > t t~ QED=0 @1 // Process: d d~ > t t~ QED=0 @1 // Process: s s~ > t t~ QED=0 @1 //-------------------------------------------------------------------------- class Sigma_sm_qq_ttx : public Sigma2Process Compactified and optimized multiprocess { public: output for MadEvent // Constructor. Sigma_sm_qq_ttx() {} // Initialize process. virtual void initProc(); // Calculate flavour-independent parts of cross section. virtual void sigmaKin(); // Evaluate sigmaHat(sHat). virtual double sigmaHat(); + Standalone Matrix Element output in // Select flavour, colour and anticolour. Fortran and C++ virtual void setIdColAcol(); ... Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 29
But the biggest advances.. … are in a new interface from FeynRules! Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 30
But the biggest advances.. … are in a new interface from FeynRules! Universal FeynRules Output (UFO) ALOHA Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 31
The biggest advances ● Universal FeynRules Output (UFO) – I ncludes color and Lorentz structure – Allows for complete specification of effective/non- renormalizable vertices – Allows for automatic output of model parameter calculations for any model and language ● Automatic Language-independent Output of Helicity Amplitudes (ALOHA) – Automatic generation the necessary helicity amplitude code for any new model (including effective theories, multi-fermion vertices,...) in Fortran/C++/Python/... See talk by Olivier Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 32
Universal FeynRules Output (UFO) lorentz.py: particles.py: VVV1 = Lorentz(name = 'VVV1', G = Particle(pdg_code = 21, spins = [ 3, 3, 3 ], name = 'G', Structure = antiname = 'G', 'P(3,1)*Metric(1,2) - spin = 3, P(3,2)*Metric(1,2) - color = 8, P(2,1)*Metric(1,3) + mass = 'ZERO', P(2,3)*Metric(1,3) + width = 'ZERO', P(1,2)*Metric(2,3) - texname = 'G', P(1,3)*Metric(2,3)') antitexname = 'G', line = 'curly', couplings.py: charge = 0, GC_4 = Coupling(name = 'GC_4', LeptonNumber = 0, value = '-G', GhostNumber = 0) order = {'QCD':1}) vertices.py: V_2 = Vertex(name = 'V_2', particles = [ P.G, P.G, P.G ], color = [ 'f(1,2,3)' ], lorentz = [ L.VVV1 ], couplings = {(0,0):C.GC_4}) Johan Alwall - The Vision of MG/FR Johan Alwall - The Vision of MG/FR 33
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