<chapter name="Index"> 
 
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<h2>PYTHIA 8 Index</h2> 
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<button class="expand" style="font-size:20px;">Program Overview</button> 
<div class="panel"> 
<aidx href="Frontpage">Frontpage</aidx><br/> 
<aidx href="ProgramFlow">Initialization &amp; Program Flow</aidx><br/> 
<aidx href="SettingsScheme">Settings Scheme</aidx><br/> 
<aidx href="ParticleDataScheme">Particle Data Scheme</aidx><br/> 
</div> 
 
<button class="expand" style="font-size:20px;">Getting Started</button> 
<div class="panel"> 
<aidx href="GettingStarted">Resources for New Users</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="SampleMainPrograms">Sample Main Programs</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="ExampleKeywords">Examples by Keyword</aidx><br/> 
</div> 
 
<button class="expand" style="font-size:20px;">Setup Run Tasks</button> 
<div class="panel"> 
<aidx href="MainProgramSettings">Main-Program Settings</aidx><br/> 
<aidx href="MasterSwitches">Master Switches</aidx><br/> 
<aidx href="RandomNumberSeed">Random-Number Seed</aidx><br/> 
<aidx href="Tunes">Tunes</aidx><br/> 
<aidx href="Logging">Logging and Diagnostics</aidx><br/> 
<aidx href="ErrorChecks">Error Checks</aidx><br/> 
<aidx href="Parallelism">Parallelism</aidx><br/> 
<aidx href="Plugins">Plugins</aidx><br/> 
</div> 
 
<button class="expand" style="font-size:20px;">Beams</button> 
<div class="panel"> 
<aidx href="BeamParameters">Beam Parameters</aidx><br/> 
<aidx href="PDFSelection">PDF Selection</aidx><br/> 
<aidx href="Photoproduction">Photoproduction</aidx><br/> 
<aidx href="HeavyIons">Heavy Ion Collisions</aidx><br/> 
</div> 
 
<button class="expand" style="font-size:20px;">Process Selection</button> 
<div class="panel"> 
<aidx href="StandardModelParameters">Standard-Model Parameters</aidx><br/> 
<aidx href="CouplingsAndScales">Couplings and Scales</aidx><br/> 
<aidx href="ProcessSelection">Hard Processes</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="QCDHardProcesses">Hard QCD</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="ElectroweakProcesses">Electroweak</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="OniaProcesses">Onia</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="TopProcesses">Top</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="FourthGenerationProcesses">Fourth Generation</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="HiggsProcesses">Higgs</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="SUSYProcesses">SUSY</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="NewGaugeBosonProcesses">New Gauge Bosons</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="LeftRightSymmetryProcesses">Left-Right Symmetry</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="LeptoquarkProcesses">Leptoquark</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="CompositenessProcesses">Compositeness</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="HiddenValleyProcesses">Hidden Valleys</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="ExtraDimensionalProcesses">Extra Dimensions</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="DarkMatterProcesses">Dark Matter</aidx><br/> 
<aidx href="PhaseSpaceCuts">Phase Space Cuts</aidx><br/> 
<aidx href="SecondHardProcess">Second Hard Process</aidx><br/> 
<aidx href="TotalCrossSections">Total Cross Sections</aidx><br/> 
<aidx href="QCDSoftProcesses">Soft QCD Processes</aidx><br/> 
<aidx href="QCDLowEnergyProcesses">Low-energy QCD Processes</aidx><br/> 
<aidx href="MultipartonInteractions">Multiparton Interactions</aidx><br/> 
<aidx href="Diffraction">Diffraction</aidx><br/> 
</div> 
 
<button class="expand" style="font-size:20px;">Interfaces to External 
Hard Processes</button> 
<div class="panel"> 
<aidx href="LHA">Les Houches Accord (LHA)</aidx><br/> 
<aidx href="LHEF">Les Houches Event Files</aidx><br/> 
<aidx href="SemiInternalProcesses">Semi-Internal Processes</aidx><br/> 
<aidx href="MadGraph5Processes">MadGraph5 Processes</aidx><br/> 
<aidx href="HelacOniaProcesses">HelacOnia Processes</aidx><br/> 
<aidx href="AlpgenEventInterface">Alpgen Event Interface</aidx><br/> 
</div> 
 
<button class="expand" style="font-size:20px;">Parton Showers</button> 
<div class="panel"> 
<aidx href="PartonShowers">Shower Model Selection</aidx><br/> 
<aidx href="SimpleShowers">The Simple Shower</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="TimelikeShowers">Timelike Showers</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="SpacelikeShowers">Spacelike Showers</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="OniaShowers">Onia Showers</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="WeakShowers">Weak Showers</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="Variations">Automated Variations and Enhanced Emissions</aidx> 
<br/> 
<aidx href="Vincia">Antenna Showers (Vincia)</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="VinciaQCD">QCD Showers</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="VinciaEW">QED/EW Showers</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="VinciaMECs">ME Corrections</aidx><br/> 
<aidx href="ImplementNewShowers">Implement New Showers</aidx><br/> 
</div> 
 
<button class="expand" style="font-size:20px;">Matching and Merging</button> 
<div class="panel"> 
<aidx href="MatchingAndMerging">Matching and Merging</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="POWHEGMatching">POWHEG Matching</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="aMCatNLOMatching">aMC@NLO Matching</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="JetMatching">MLM Jet Merging</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="CKKWLMerging">CKKW-L Merging</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="VinciaMerging">MESS Merging (Vincia)</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="UMEPSMerging">UMEPS Merging</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="NLOMerging">NLO Merging</aidx><br/> 
<aidx href="MergingVariations">Merging Variations</aidx><br/> 
<aidx href="ImplementNewMatching">Implement New Schemes</aidx><br/> 
</div> 
 
<button class="expand" style="font-size:20px;">Particles &amp; Decays</button> 
<div class="panel"> 
<aidx href="ParticleData">Particle Data</aidx><br/> 
<aidx href="HadronWidths">Mass-dependent Hadron Widths</aidx><br/> 
<aidx href="ResonanceDecays">Resonance Decays</aidx><br/> 
<aidx href="ParticleDecays">Hadron &amp; Tau Decays</aidx><br/> 
<aidx href="SemiInternalResonances">Semi-Internal Resonances</aidx><br/> 
<aidx href="ExternalDecays">External Decays</aidx><br/> 
</div> 
 
<button class="expand" style="font-size:20px;">Hadronization</button> 
<div class="panel"> 
<aidx href="HadronizationOverview">Hadronization Overview</aidx><br/> 
<aidx href="BeamRemnants">Beam Remnants</aidx><br/> 
<aidx href="ColourReconnection">Colour Reconnection</aidx><br/> 
<aidx href="PartonVertexInformation">Parton Vertex Information</aidx><br/> 
<aidx href="StringFragmentation">Lund String Fragmentation</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="FlavourSelection">Flavour Selection</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="PTSelection">pT Selection</aidx><br/> 
&nbsp;&nbsp;--&nbsp;&nbsp; 
<aidx href="ZSelection">z Selection</aidx><br/> 
<aidx href="ThermalFragmentation">Thermal Fragmentation</aidx><br/> 
<aidx href="HadronizationVariations">Hadronization Variations</aidx><br/> 
<aidx href="RopeHadronization">Rope Hadronization</aidx><br/> 
<aidx href="ClosePacking">Close-Packing</aidx><br/> 
<aidx href="HadronVertexInformation">Hadron Vertex Information</aidx><br/> 
<aidx href="HadronicRescattering">Hadronic Rescattering</aidx><br/> 
<aidx href="RHadrons">R-hadrons</aidx><br/> 
<aidx href="BoseEinsteinEffects">Bose-Einstein Effects</aidx><br/> 
<aidx href="DeuteronProduction">Deuteron Production</aidx><br/> 
<aidx href="HadronLevelStandalone">Hadron-Level Standalone</aidx><br/> 
<aidx href="ImplementNewFragmentation">Implement New Fragmentation</aidx><br/> 
</div> 
 
<button class="expand" style="font-size:20px;">Study Output</button> 
<div class="panel"> 
<aidx href="FourVectors">Four-Vectors</aidx><br/> 
<aidx href="ParticleProperties">Particle Properties</aidx><br/> 
<aidx href="EventRecord">Event Record</aidx><br/> 
<aidx href="EventInformation">Event Information</aidx><br/> 
<aidx href="EventStatistics">Event Statistics</aidx><br/> 
<aidx href="EventAnalysis">Event Analysis</aidx><br/> 
<aidx href="CrossSectionsAndWeights">Cross Sections and Weights</aidx><br/> 
<aidx href="Histograms">Histograms</aidx><br/> 
<aidx href="AdvancedUsage">Advanced Usage</aidx><br/> 
</div> 
 
<button class="expand" style="font-size:20px;">Other Interfaces</button> 
<div class="panel"> 
<aidx href="SUSYLesHouchesAccord">Susy Les Houches Accord (SLHA)</aidx><br/> 
<aidx href="LHAHDF5">HDF5 Les Houches Accord (LHAHDF5)</aidx><br/> 
<aidx href="HepMCInterface">HepMC Interface</aidx><br/> 
<aidx href="UserHooks">User Hooks</aidx><br/> 
<aidx href="BeamShape">Beam Shape</aidx><br/> 
<aidx href="PartonDistributions">Parton Distributions</aidx><br/> 
<aidx href="JetFinders">Jet Finders</aidx><br/> 
<aidx href="RandomNumbers">Random Numbers</aidx><br/> 
<aidx href="RIVETusage">RIVET usage</aidx><br/> 
<aidx href="ROOTusage">ROOT usage</aidx><br/> 
<aidx href="PythonInterface">Python Interface</aidx><br/> 
</div> 
 
<button class="expand" style="font-size:20px;">Reference Material</button> 
<div class="panel"> 
<aidx href="UpdateHistory">Update History</aidx><br/> 
<aidx href="Bibliography">Bibliography</aidx><br/> 
<aidx href="Glossary">Glossary</aidx><br/> 
<aidx href="Version">Version</aidx> <br/> 
</div> 
 
<button class="expand" style="font-size:20px;">Separate Documents</button> 
<div class="panel"> 
<a href="../pdfdoc/pythia8300.pdf" target="page">Introduction</a><br/> 
<a href="../pdfdoc/worksheet8312.pdf" target="page">Worksheet</a> 
</div> 
 
<button class="expandAll" style="font-size:20px;">All</button> 
 
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</chapter> 
 
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