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Version: 1.2

ROOT tree output

The EPOS4 tree output obtained in the .root files, generated by enabling the -root flag, is documented in the developers manual. Here I will include a list of the main components that you will find by opening the output.
Before starting the list, however, I need to mention that two cloned versions of the same trees are going to be found in the .root file, which are equivalent from my understanding.

teposhead​

  • iversn → EPOS version number
  • laproj → atomic number projectile
  • maproj → mass number projectile
  • latarg → atomic number target
  • matarg → mass number target
  • engy → energy in the cms in GeV
  • nfull → number of full events
  • nfreeze → number of freeze outs per full event (to increase stat)

teposevent​

  • px → p_x of particle
  • py → p_y of particle
  • pz → p_z of particle
  • e → energy of particle
  • x → x component of formation point
  • y → y component of formation point
  • z → z component of formation point
  • t → formation time
  • id → EPOS particle ID
  • ist → particle status (hadron last generation (0) or not (1); other numbers refer to partons, Pomerons, etc)
  • ity → type of particle origin (20-29 from soft strings, 30-39 from hard strings, 40-59 from remnants, 60 from fluid)
  • ior → index of father (resonance decay products have only a father)
  • jor → index of mother (mothers are needed for example for strings: the partons between ior and jor constitute the string)
  • np → number of particles
  • bim → impact parameter (usually other choices are possible)