TGlauberMC: A ROOT-based implementation of the PHOBOS Glauber Monte Carlo

"Glauber" models are used to calculate geometric quantities in the initial state of heavy ion collisions, such as impact parameter, number of participating nucleons and initial eccentricity. The four RHIC experiments have different methods for Glauber Model calculations, leading to similar results for various geometric observables.

The original version, which was written by B. Alver (MIT), M. Baker (BNL), C. Loizides (MIT) and P. Steinberg (BNL), is described in arXiv:0805.4411. Details about the implementation of the Monte Carlo based Glauber Model calculation used by the PHOBOS experiment, and the assumptions that underlie the calculation are described. A user's guide is provided for running various calculations.

An updated version (v2) by C. Loizides (LBNL), J. Nagle (Colorado U.), P. Steinberg (BNL) is described in arXiv:1408.2549, which includes Tritium, Helium-3, and Uranium, as well as the treatment of deformed nuclei and Glauber-Gribov fluctuations of the proton in p+A collisions.

An improved version (v3) by C. Loizides (ORNL), J. Kamin (UiC), D. d'Enterria (CERN) is described in arXiv:1710.07098, which for Pb nuclei includes separated 2-parameter Fermi distributions for protons and neutrons, and can model the nucleon degrees of freedom inside the nucleus through a lattice with a minimum nodal separation, combined with a "recentering and reweighting" procedure, that overcomes some limitations of previous MCG approaches. It includes various tables with precision results for BNL RHIC 200 GeV (AuAu, CuCu), CERN LHC (including XeXe), LHC-HE and FCC collision energies.

Please also see the review article by D. d'Enterria (CERN) and C.Loizides (ORNL). It is based on the version 3.2 of the Glauber code, with an updated parameterization for the inelastic cross section given in ROOT as

sf = new TF1("sf","[0]+[1]*pow(log(x*x),[2])",10,10000);
sf->SetParameters(28.84,0.0458,2.374);

For the latest release see the TGlauberMC downloads page.

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v3.2: 
  Incorporates changes from v2.7
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v3.1:
  Fixes related to spherical nuclei, as well as consistent set of reweighted profiles 
  for Cu, Au and Xe, see https://arxiv.org/abs/1710.07098v2
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v3.0:
  Major update to include separate profile for protons and neutrons, placement of nucleon 
  dof on lattice, as well as reweighted profiles for recentering, 
  see https://arxiv.org/abs/1710.07098
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v2.7: 
  New macro "runAndOutputLemonTree" for IP-Jazma input (1808.01276), as well as nucleon 
  configurations for He4, C, and O from wavefunction calculations, clarified use of Hulthen
  for deuteron, harmonic oscillator param for O, and new mode to use GlauberGribov also 
  in AA (enable with SetCalcAAGG)
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v2.6:
  Includes runAndCalcDens macro, as well as definition for Al, and fixes beta4 for Si2,
  see https://arxiv.org/abs/1408.2549v8
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v2.5:
  Include core/corona determination in Npart, and if requested for eccentricity,
  as well as various Xe parameterizations including deformation,
  see https://arxiv.org/abs/1408.2549v7
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v2.4: 
  Minor update to include Xenon and fix of the TGlauberMC::Draw function, 
  see see https://arxiv.org/abs/1408.2549v4
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v2.3: 
  Small bugfixes, see https://arxiv.org/abs/1408.2549v3
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v2.2:
  Minor update to provide higher harmonic eccentricities up to n=5, and the average
  nucleon--nucleon impact parameter (bNN) in tree output. 
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v2.1: 
  Minor update to include more proton pdfs, see https://arxiv.org/abs/1408.2549v2
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v2.0: 
  First major update with inclusion of tritium, Helium-3, and Uranium, as well as the 
  treatment of deformed nuclei and Glauber-Gribov fluctuations of the proton in p+A 
  collisions, see https://arxiv.org/abs/1408.2549v1
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v1.1: 
  First public release of the PHOBOS MC Glauber, see https://arxiv.org/abs/0805.4411
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The page and the code is maintained by C.Loizides. Click here in case you have questions.