Settings

The following are a list of user settings that are common to all event generators. Note that the input key is case-insensitive.

General Settings

  • Generators: A list of generators [2, 3, 4, 5, 6, 7, 8, 9, 10] whose runcards should be generated. One generator must be specified from the currently supported set of:

Generators:
  - Babayaga
  - Herwig
  - Madgraph
  - Pythia
  - Sherpa
  - Whizard

  • Model: Name of the model (default: SM)

  • SqrtS: \(\sqrt{s}\) in GeV.

  • ISRMode: Enable Initial State Radiation (ISR):

ISRMode: 1

default: 0 (turned off)

  • RandomSeed: Seed for the event generation

  • OutputFormat: Format in which the monte-carlo events will be written out to. Currently supported options are edm4hep, hepmc and lhe (default: edm4hep)

  • OutDir: The directory to which the run-cards will be saved. Current default is $PWD/Run-Cards.

  • Events: Number of Monte-Carlo events to be generated.

  • EWParamDevThreshold: threshold for issueing a warning if in the EW parameters at LO a relative deviation is larger

  • NLO: integer to turn on/off NLO with default: 0 (off)

  • Processes: A list of processes which runcards should be generated. Each process should have its own unique name. Under these headings you can specify the initial and final states, a list of pdg codes, to be generated and at what order e.g [EW,QCD].

Processes:
  Muon:
     Initial: [11, -11]
     Final: [13, -13]
  MuonNeutrino:
     Initial: [11, -11]
     Final: [14, -14]
  Tau:
     Initial: [11, -11]
     Final: [15, -15]
  TauNeutrino:
     Initial: [11, -11]
     Final: [16, -16]

Particle Data

Particle properties can be modified with respect to the default:

  • ParticleData: The user can set various particle properties such as mass and width. Note it is expected of the user to set a consistent input scheme. The particles are identified using the corresponding PDG number

ParticleData:
  25:
    mass: 125
    width: 0
  11:
    mass: 0.0005111
    width: 0
  23:
    mass: 91.1876
    width: 2.4952
  24:
    mass: 80.379
    width: 2.085

Phase Space

By default, no restrictions are applied on the available phase space. If necessary:

  • Selectors: Some basic one and two particle phasespace cuts can be set. Each will need to be set with a minimum and maximum value as well as the flavour(s) it should be applied to.

    • One Particle Selectors:

      • PT: Cut on the transverse momenta

      • ETA: Cut on the pseduorapidity

      • Y: Cut on the Rapidity

      • ET: Cut on the Transverse energy

    • Two Particle Selectors:

      • Mass: Cut on the invariant mass of two particles

      • Angle: Cut on the angular separation in radians

      • DEta: Cut on the pseudorapidity separation

      • DY: Cut on the rapidity separation

      • DPhi: Cut on the azimuthal separation in radians

      • DR: Cut on the R separation

Generator Specific Settings

Here we summarise the settings available to a subset of generators.

  • Beam Polarization: Polarized beams are available for Madgraph, Sherpa and Whizard. It can be set as follows

PositronPolarisation: 0.3
ElectronPolarisation: 0.8

  • Beamstrahlung: is turned on by specifying the type of accelerator. Allowed values are: ILC, FCC, C3, CEPC, HALFHF.

Beamstrahlung: ILC

Note that Beamstrahlung is conditional on ISRmode being on. The Beamstrahlung and SqrtS variables are used to configure the settings of the generators. For SqrtS a vicinity search (within 10GeV) is performed. In case the requested setting does not exist, a replacement setting is used and printed as a warning.

Analysis

Postgeneration analyses can be performed either using Rivet [11, 12] and/or key4hep [13, 14]

Analysis:
  Tools: [key4hep, rivet]
  RivetAnalysis: [MC_XS, MC_ZINC,...]
  RivetPath: /path/to/analysis