clas-stringspinner Usage Guide

$install_dir/bin/clas-stringspinner --help

USAGE: clas-stringspinner [OPTIONS]...

  --verbose                        verbose printout
  --help                           print this usage guide


OUTPUT FILE CONTROL:

  --num-events NUM_EVENTS          number of events
                                   default: 10000

  --count-before-cuts              if used, --num-events will be the number of events
                                   before any cuts; the Lund file will thus have less
                                   than --num-events events
                                   default: number of output events == --num-events

  --out-file OUTPUT_FILE           output file name
                                   default: "clas-stringspinner.dat"

  --float-precision PRECISION      floating point numerical precision for output files
                                   default: 5


BEAM AND TARGET PROPERTIES:

  --beam-energy ENERGY             electron beam energy [GeV]
                                   default: 10.6041

  --target-type TARGET_TYPE        target type, one of:
                                     proton
                                     neutron
                                   default: "proton"

  --pol-type POLARIZATION_TYPE     beam and target polarization types
                                   - two characters: beam and target
                                   - types: 'U' = unpolarized
                                            'L' = longitudinally polarized
                                            'T' = transversely polarized
                                   default: "UU"

  --beam-spin BEAM_SPIN            the spin of the beam leptons
                                   - if longitudinally polarized ('L'):
                                     'p' = spin along +z axis
                                     'm' = spin along -z axis
                                   - if transversely polarized ('T'):
                                     'p' = spin along +y axis
                                     'm' = spin along -y axis
                                   - if unpolarized ('U'): no effect

  --target-spin TARGET_SPIN        the spin of the target nucleons
                                   - same usage as --beam-spin, applied to target


GENERATOR PARAMETERS:

  Configuration parameters may be loaded from a configuration file from:
    https://github.com/JeffersonLab/clas-stringspinner/tree/main/config
  Use the --config option to choose one of them, and use the options below
  to set additional specific parameters

  --config CONFIG_FILE_NAME        Pythia configuration file
                                   - choose a configuration file from one of the following:
                                            clas12.cmnd
                                   default: "clas12.cmnd"

  --seed SEED                      random number generator seed, where:
                                   - Pythia's default seed: -1
                                   - seed based on time:  0
                                   - fixed seed:  1 to 900000000
                                   default: -1

  --glgt-mag GLGT_MAGNITUDE        StringSpinner parameter |G_L/G_T|
                                   - fraction of longitudinally polarized vector mesons:
                                       f_L = |G_L/G_T|^2 / ( 2 + |G_L/G_T|^2 )
                                       with 0 <= f_L <= 1
                                   default: 0.2

  --glgt-arg GLGT_ARGUMENT         StringSpinner parameter theta_{LT} = arg(G_L/G_T)
                                   - related to vector meson oblique polarization
                                   - range: -PI <= theta_{LT} <= +PI
                                   default: 0


CUTS FOR EVENT SELECTION:

  --cut-string OBJ1,OBJ2           filter by Lund strings, where OBJ1 and OBJ2 are PDG
                                   codes of quarks or diquarks;
                                   - PDG codes must be separated by a comma, with no spaces
                                   - examples:
                                       --cut-string 2,2101  # selects 'u === (ud)_0' strings
                                       --cut-string 0,0     # disable string selection
                                   default: 2,2101

  --cut-inclusive PDG_CODES...     only allow events which have a least these particles
                                   - delimit by commas
                                   - repeat PDG codes to require more than one
                                   - example: 1 pi- and 2 pi+s: --cut-inclusive -211,211,211
                                   default: no cut

  --cut-theta MIN,MAX              if set, along with --cut-inclusive, this requires the theta
                                   of all particles used in --cut-inclusive to have
                                   MIN <= theta <= MAX, with units in degrees


OPTIONS FOR OSG COMPATIBILITY:

  --trig NUM_EVENTS                same as --num-events
  --docker                         unused