Jiayi Wang1, Jianling Tang2, Chutian Gong3
1St.Olaf College, Northfield MN, 55057, USA
2The Australian National University, Canberra, ACT 2600, Australia
3The Second High School Attached to Beijing Normal University (International campus) Beijing, 100192, China
Glauber model is a model used to describe heavy ion collision process. In this paper, we describe an implementation of a Monte Carlo based Glauber Model calculation used for the PHOBOS experiment, which simulates the collision of two heavy nuclei. The nucleon distribution in two initial Pb nuclei is parameterized with Woods-Saxon. The energy profile is √(SNN )=5.5TeV and inelastic cross-section area, i.eσNN= 72mb. Geometric quantities such as impact parameter(b), the participant elliptical and triangular eccentricities (ε2, ε3) are studied and presented graphically and quantitatively in this paper. The results for collisions of Pb-Pb are compared with other Glauber model calculations which agrees with the results from other studies to a great extent. In this simulation, a decline trend of ε2 and ε3 is observed with increasing Npart. The centralities of peripheral events (40 to 50 percent centrality) are ε2 ranging from 0.5 to 0.4 and ε3 being roughly 0.3. The ratio of ε3 to ε2 is roughly 0.5 at Npart=0 and 1 at Npart=416 (a hundred percent centrality), showing the significance of triangular flow of the area of intersection. The model can also be used to predict geometric quantities in the LHC experiments and other collision processes.
Glauber Model, Monte Carlo, Eccentricity, Heavy ion collision, Pb nuclei
Jiayi Wang, Jianling Tang, Chutian Gong. Monte Carlo Based Glauber Model in Pb-Pb Collisions at LHC. The Frontiers of Society, Science and Technology (2021) Vol. 3, Issue 1: 145-150. https://doi.org/10.25236/FSST.2021.030123.
 B. Alver and G. Roland, “Collision-geometry fluctuations and triangular flow in heavy-ion collisions,” Physical Re- view C, vol. 81, no. 5, p. 054905, 2010.
 M. L. Miller, K. Reygers, S. J. Sanders, and P. Stein- berg, “Glauber modeling in high-energy nuclear colli- sions,” Annual Review of Nuclear and Particle Science, vol. 57, p. 205–243, Nov 2007.
 M. Rybczyn ́ski and W. Broniowski, “Glauber monte carlo predictions for ultrarelativistic collisions with 16O,” Phys. Rev. C, vol. 100, p. 064912, Dec 2019.
 B. Alver, M. Baker, C. Loizides, and P. Steinberg, “The phobos glauber monte carlo,” 2008.
 J. Klay, “Mcg.” https://github.com/MCGlauber/MCG, 2014.
 J. Tang and J. Wang, “Glauber model implementation.” https://github.com/JianlingTang/Glauber_ implementation, 2020.
 S. Chatrchyan, V. Khachatryan, A. Sirunyan, A. Tu- masyan, W. Adam, T. Bergauer, M. Dragicevic, J. Er ̈o, C. Fabjan, M. Friedl, et al., “Study of high-ptcharged particle suppression in pbpb compared to pp collisions at √S_NN = 2.76 TeV,” The European Physical Journal C, vol. 72, no. 3, p. 1945, 2012.