Version: SMASH-2.1
ASCII IC Output

The ASCII initial conditions output (SMASH_IC.dat) contains a list of particles on a hypersurface of constant proper time. This output is formatted such that it is directly compatible with the vHLLE hydrodynamics code (I. Karpenko, P. Huovinen, M. Bleicher: Comput. Phys. Commun. 185, 3016 (2014)). As a consequence, spectators are not written to the ASCII IC output as they would need to be excluded anyways in order to initialize the hydrodynamics evolution. Note though that for all other output formats the full particle list is printed to the IC output, including spectators. The particle data is provided in the computational frame. For further details, see Initial Conditions.

The ASCII initial conditions output is formatted as follows:
Header

# **smash_version** initial conditions: hypersurface of constant proper time
# tau x y eta mt px py Rap pdg charge
# fm fm fm none GeV GeV GeV none none e

The header consists of 3 lines starting with a '#', containing the following information:

  1. SMASH-version and the information, that 'initial conditions' are provided
  2. The header with all column names
  3. The units of all column quantities

Output block header

The ASCII initial conditions output is, similar to the OSCAR output, based on a block structure, where each block consists of 1 event. The header for a new event is structured as follows:

# event ev_num start

where

  • ev_num: The number of the current event

Note that 'event' and 'start' are no variables, but words that are printed in the header.

Particle line

The particle lines are formatted as follows:

tau x y eta mt px py Rap pdg charge

where

  • tau: Proper time of the particle
  • x, y: Cartesian x and y coordinates of the particle
  • eta: Space-time rapidity of the particle
  • mt: Transverse mass of the particle
  • px, py: x and y components of the particle's momentum
  • Rap: Momentum space rapidity of the particle
  • pdg: PDG code of the particle (see http://pdg.lbl.gov/). It contains all quantum numbers and uniquely identifies its type. every particle in the event.
  • charge: electric charge of the particle

Event end line

The end of an event is indicated by the following line:

# event ev_num end

where

  • ev_num: The number of the current event

Note that 'event' and 'end' are no variables, but words that are printed in the header.

Note
If SMASH is run with test particles (necessary e.g. for potentials), the ASCII output will contain Ntest * Npart particle entries. Remember to weigh each of those particles with 1/Ntest.